Methods Index
164 Methods, Each with Its Source
Built from the engine's capability report and its citations. A method the engine refuses is never listed as offered.
Checked 37Checked (exact) 4Partial 106Unverified 16In build, not released 1
Checked reproduces printed values Checked (exact) no printed value exists; checked against exact mathematics or brute force Partial code exists, unchecked parts badged in the app Unverified built, no printed check yet In build, not released in build, not released (not in the installed engine)
| Method | Domain | Support | Since | Primary Sources |
|---|---|---|---|---|
| Hartree-Fock (RHF, UHF)Energies, analytic gradients, optimisation, frequencies, scans, orbitals and stability analysis. | Quantum Chemistry | Checked | 0.1 | Roothaan 1951; Pople, Nesbet 1954; Seeger, Pople 1977 |
| LDA (SVWN5, SVWN-RPA, SPW92)Local density functionals in RKS and UKS form with analytic gradients. | Quantum Chemistry | Checked | 0.7.0 | Vosko, Wilk, Nusair 1980; Perdew, Wang 1992 |
| GGA (BLYP, PBE, HF-LYP)Generalised gradient functionals with analytic gradients and Hessians. | Quantum Chemistry | Checked | 0.7.0 | Becke 1988; Lee, Yang, Parr 1988; Perdew, Burke, Ernzerhof 1996 |
| Global hybrids (B3LYP, PBE0)B3LYP in two explicit VWN forms, and PBE0. Compare B3LYP totals only within one VWN form. | Quantum Chemistry | Checked | 0.7.14 | Stephens et al. 1994; Adamo, Barone 1999; Hertwig, Koch 1997 |
| Range-separated hybrids (wB97, wB97X, wB97X-D, CAM-B3LYP)Long-range corrected hybrids for charge transfer and excited states. | Quantum Chemistry | Partial | 0.7.21 | Chai, Head-Gordon 2008; Yanai, Tew, Handy 2004 |
| wB97X-V and wB97M-V with VV10 nonlocal correlationEnergy, potential and analytic gradient of wB97X-V and, since 1.5.0, wB97M-V. Standalone VV10, B97M-V and VV10 Hessians are not offered. No stability analysis for wB97X-V or wB97M-V (no response kernel). | Quantum Chemistry | Unverified | 1.2.0 | Mardirossian, Head-Gordon 2014; Vydrov, Van Voorhis 2010 |
| Meta-GGA (TPSS, TPSSh, M06, M06-2X, M06-L, SCAN, rSCAN, r2SCAN)Meta-GGA energies, gradients and optimisation including the kinetic energy density term. Frequencies by finite differences of analytic gradients, with a blocked grid code that is much faster since 1.9.8. No SCF stability analysis for meta-GGAs yet (the kernel is not built). Grid sensitivity is high: use Fine or SuperFine. | Quantum Chemistry | Partial | 0.7.65 | Tao et al. 2003; Zhao, Truhlar 2008; Sun, Ruzsinszky, Perdew 2015; Furness et al. 2020 |
| Double hybrids (B2PLYP, DSD-BLYP)Double-hybrid energies with frozen-core options. Analytic gradients, optimisation and frequencies are offered through the row Double-hybrid analytic gradients. D3 and D4 are not offered with double hybrids. | Quantum Chemistry | Partial | 0.7.31 | Grimme 2006; Kozuch, Martin 2011 |
| Double-hybrid analytic gradientsB2PLYP and DSD-BLYP gradients with the Kohn-Sham Z-vector, for optimisation and frequencies. No analytic double-hybrid Hessian. | Quantum Chemistry | Partial | 1.3.0 | Neese, Schwabe, Grimme 2007 |
| Dispersion (D2, XDM, built-in wB97X-D)Grimme D2 for PBE and BLYP and the exchange-hole dipole moment model with gradients. D2: the element parameters are checked against Grimme 2006 Table 1; that paper prints no D2 energies, so energies are checked against an independent evaluation of its equations. XDM: free-atom C6, C8 and C10 agree with Becke, Johnson 2007 within 1 to 3 % and the He2 dispersion energy with Johnson, Becke 2006 Table III within 2 %. The built-in wB97X-D dispersion term has no printed check yet. | Quantum Chemistry | Checked | 0.7.15 | Grimme 2006; Becke, Johnson 2007; Johnson, Becke 2006 |
| DFT-D3(0), D3(BJ) and DFT-D4 on published reference dataTwo-body D3 with zero damping (D3(0), since 1.9.4, from the published C6 and pair-radius tables), D3(BJ) and D4 energies and gradients for Z 1-86. The three-body variants (d3-atm, d3bj-atm) are refused: s9 and s42 are not printed in any held source. D3(BJ) runs without ATM. D3(0) agrees with an independent program; D3(BJ) and D4 have no printed check yet. | Quantum Chemistry | Partial | 1.9.0 | Grimme et al. 2010; Grimme, Ehrlich, Goerigk 2011; Caldeweyher et al. 2019 |
| GFN1-xTB, GFN2-xTB and DFTB3/3OBTight-binding energies, gradients, optimisation and frequencies: GFN1-xTB and GFN2-xTB for Z 1-86, and DFTB3 and DFTB2 with the 3OB set (Br C Ca Cl F H I K Mg N Na O P S Zn). Not built: implicit solvation, periodic boundaries, spin-polarised xTB and DFTB, GFN-FF, PM6, PM7 and an analytic Hessian. Checked against reference energies and gradients of the method authors' test cases and the printed parameter tables, not against printed results. | Quantum Chemistry | Partial | 1.9.0 | Grimme, Bannwarth, Shushkov 2017; Bannwarth, Ehlert, Grimme 2019; Gaus, Cui, Elstner 2011 |
| Molecular GW and BSEG0W0 and evGW quasiparticle energies, ionisation potentials, electron affinities and gaps, and Bethe-Salpeter singlet and triplet excitations with oscillator strengths on an RHF or RKS reference. Molecules only and closed shell; no periodic GW or BSE and no dynamical BSE kernel. G0W0@PBE ionisation potentials reproduce van Setten et al. 2015 Table 2 (He, Ne). | Excited States and Spectroscopy | Checked | 1.9.0 | Hedin 1965; van Setten et al. 2015 |
| Real-time TDDFTReal-time TDHF and TDDFT propagation with a second-order Magnus propagator and predictor-corrector, delta-kick absorption (dipole strength and the TRK sum), dipole time series and an optional continuous field. Closed-shell molecules; LDA, GGA and global hybrids only. Open-shell, range-separated, meta-GGA and VV10 functionals are refused. Selftest identities passed in the 1.9.0 gate; no printed spectrum reproduced yet. | Excited States and Spectroscopy | Unverified | 1.9.0 | |
| Radiative, intersystem and reverse intersystem crossing ratesFluorescence and phosphorescence radiative rates and lifetimes in the Condon limit with a triplet sublevel Boltzmann average, and golden-rule intersystem crossing and reverse intersystem crossing rates with El-Sayed classification, from spin-orbit couplings. Marcus-Levich-Jortner high-temperature form only; no spin-orbit quasi-degenerate phosphorescence dipoles; spin-orbit couplings have no solvent. Radiative rates reproduce Strickler and Berg 1962 Table I (11 lifetimes, largest relative difference 0.07%); intersystem crossing rates are checked at formula level only (Englman and Jortner 1970). | Excited States and Spectroscopy | Partial | 1.9.0 | de Souza et al. 2019; Marian 2012; Strickler, Berg 1962; Englman, Jortner 1970 |
| Conical intersections, MECP and derivative couplingsMinimum-energy crossing points between states of different spin (MECP) and conical intersection points of the same spin (MECI) by a projected mean-energy gradient with a constraint step, derivative coupling vectors between singlet TDA and CIS states by finite differences, and numerical gradients of EOM-CCSD, ADC(2) and CC2 states. Crossings up to 30 atoms, couplings up to 20 atoms, correlated-state gradients up to 8 atoms. States from an SCF ground state or TDA/TDDFT roots with LDA, GGA, global hybrids or Hartree-Fock. Couplings and gradients are numerical, not analytic. No printed crossing geometry reproduced yet. | Excited States and Spectroscopy | Unverified | 1.9.0 | Jensen 2017; Hammes-Schiffer, Tully 1994 |
| Plane-wave materials: elastic constants, EOS, Bader, slabs, PDOSClamped-ion elastic constants, equation of state, Bader charges, work functions, slabs and projected DOS. Silicon lattice constant and elastic constants (clamped and relaxed c44) compared with Nielsen and Martin 1985 Table I, with a different pseudopotential, so differences of up to 8% remain (elastic constants within 6%, bulk modulus 8%). Bader charges, work functions, slabs and PDOS are not checked against printed values. | HPC and Clusters | Partial | 1.9.0 | Nielsen, Martin 1985 |
| Protein and ligand preparation, pocketsProtein preparation with residue pKa, ligand tautomers, ionisation and stereoisomers, and pocket detection. Side-chain rebuilding, flips and loop modelling are refused. | Cheminformatics | Unverified | 1.9.0 | Olsson et al. 2011 |
| Polarisable and materials force fields, ion setsDrude and Thole polarisation, Stillinger-Weber, Tersoff and EAM potentials, Joung-Cheatham and Li-Song-Merz ion sets. Tersoff silicon c11 and c12 reproduce Tersoff 1988; c44 is not computed. Drude, Thole, Stillinger-Weber, EAM and the ion sets are not yet checked against printed values. | Molecular Mechanics and Dynamics | Checked | 1.9.0 | Joung, Cheatham 2008; Li, Song, Merz 2015; Tersoff 1988 |
| System builders and trajectory analysisSolvent boxes with ions, lipid bilayers, polymers, amorphous cells, crystal supercells, slabs and nanoparticles; radius of gyration, SASA, DSSP, PCA, clustering and NetCDF trajectories. Lipid, ion and area-per-lipid parameters are yours. No space-group generation from a symbol, no Wulff shapes and no surface relaxation. | Molecular Mechanics and Dynamics | Unverified | 1.9.0 | |
| Global optimisation, crystal structure prediction, kinetic Monte CarloBasin and minima hopping, genetic search, crystal structure prediction in eight common space groups, and lattice kinetic Monte Carlo on square and triangular lattices. Crystal candidates are exported as CIF for ranking with another tool; ranking inside the search uses force fields only. Lattice kinetic Monte Carlo has no lateral interactions. | Thermochemistry and Kinetics | Unverified | 1.9.0 | |
| Automated reaction path discoveryArtificial force induced reaction searches on the quantum chemistry energy and gradient with climbing-image NEB refinement, reaction network exploration and protomer enumeration. Artificial force follows Maeda and Morokuma 2010 Eq. 1 and 2, with the collision energy gamma as input. GSM string growth is not built. No discovered network reproduced against a printed one yet. | Thermochemistry and Kinetics | Partial | 1.9.0 | Jensen 2017; Dugundji, Ugi 1973; Maeda, Morokuma 2010 |
| MP2 and SCS-MP2Conventional and RI-MP2 energies, analytic gradient and MP2 geometry optimisation. Frequencies by finite differences of analytic gradients (no analytic Hessian); refused with counterpoise, solvation or a functional. The printed-value check covers conventional frozen-core MP2 total energies only (Weigend, Haser 1997 Table 3). RI-MP2 has no printed check yet: it is compared with conventional MP2 for one molecule (water, generated auxiliary basis, difference below 1e-4 Eh). | Quantum Chemistry | Checked | 0.7.23 | Moller, Plesset 1934; Frisch, Head-Gordon, Pople 1990; Weigend, Haser 1997; Grimme 2003 |
| MP3 and MP4(SDQ), MP4(SDTQ)Higher-order perturbation energies on RHF and UHF references. Energies only. MP4(SDTQ) and MP3 match Frisch, Pople, Binkley 1984 Table VI; the MP4(SDQ) partial sum is not printed there and is checked by size consistency. The 6-31G(d,p) N2 row of that table is matched at R(NN) 1.1160 A, not at the printed 1.10585 A. | Quantum Chemistry | Checked | 1.3.0 | Krishnan, Pople 1978; Frisch, Krishnan, Pople 1980; Frisch, Pople, Binkley 1984 |
| CCSD and CCSD(T)Coupled cluster energies for small systems on RHF and UHF references. Energies only. Printed-value checks: RHF-CCSD for BeH2 (Purvis, Bartlett 1982 Table VII, in the basis and at the geometry printed there; our CCSD energy is 1e-5 Eh below the printed value) and UHF-CCSD and UHF-CCSD(T) for the CN radical (Watts, Gauss, Bartlett 1993 Table VII, DZP basis and bond lengths of the paper), all electrons correlated. CCSD(T) on an RHF reference and frozen-core energies are checked by exact identities (closed-shell UHF equals RHF, the triples terms against exact perturbation theory, full CI for two electrons), not against printed values. | Quantum Chemistry | Checked | 0.7.65 | Purvis, Bartlett 1982; Raghavachari et al. 1989; Watts, Gauss, Bartlett 1993 |
| QCISD and QCISD(T)Quadratic configuration interaction energies, the correlation step of G3. Energies only. | Quantum Chemistry | Partial | 1.3.0 | Pople, Head-Gordon, Raghavachari 1987 |
| CASCI and CASSCFMulticonfigurational energies with optimised active-space orbitals, closed and open shells. | Quantum Chemistry | Partial | 0.7.65 | Roos, Taylor, Siegbahn 1980 |
| NEVPT2 (SC and PC)Strongly and partially contracted n-electron valence perturbation theory on CASSCF. | Quantum Chemistry | Partial | 0.9.0 | Angeli et al. 2001; Angeli, Cimiraglia, Malrieu 2002 |
| CASPT2 (single state)Second-order perturbation theory on a CASSCF reference. Multistate CASPT2 is listed separately below. | Quantum Chemistry | Partial | 0.9.0 | Andersson et al. 1990; Andersson, Malmqvist, Roos 1992 |
| Semiempirical MNDO, AM1, PM3NDDO energies, heats of formation and optimisation for closed shells. PM6 is refused: its printed tables do not reproduce PM6. | Quantum Chemistry | Checked | 1.1.0 | Dewar, Thiel 1977; Dewar et al. 1985; Stewart 1989 |
| Basis sets: Pople, def2, Dunning, pcseg and F12STO-3G, 3-21G and 32 Pople sets (6-31G and 6-311G families up to 6-311++G(3df,2pd)), G3Large, def2 SV(P) to QZVPP and the diffuse def2 sets (SVPD to QZVPPD), Dunning cc-pVXZ and aug-cc-pVXZ (X = D, T, Q; Z = 5 for H and He), cc-pCVXZ (X = D, T, Q), pcseg-n and aug-pcseg-n (n = 0 to 4), F12 and RI-fit sets (78 in all), or your own basis to g functions. Element coverage differs by set: cc-pV5Z and aug-cc-pV5Z cover H and He only, cc-pVQZ and pcseg-3 stop short of some elements, and the Pople and def2 sets cover H to Kr. A set that lacks an element is refused. | Quantum Chemistry | Checked | 0.1 | Hehre, Stewart, Pople 1969; Weigend, Ahlrichs 2005; Dunning 1989; Kendall, Dunning, Harrison 1992; Jensen 2014; Pritchard et al. 2019 |
| DFT integration grids: Coarse, Normal, Fine, TA4 and SuperFineSuperFine is 150 radial points by 974 angular points per atom, unpruned. Atomic size adjustment (Becke; Treutler, Ahlrichs) is on for Fine and SuperFine. Optimise and frequencies report the grid points and electrons on the grid. Coarse and Normal keep the plain Becke partition: measured on trans-HCOOH, a soft torsion differs from SuperFine by 2 to 14 cm-1 there. Use Fine or SuperFine for Minnesota and other grid-sensitive functionals. | Quantum Chemistry | Partial | 1.9.4 | Becke 1988; Treutler, Ahlrichs 1995; Laikov 1999 |
| Finite-difference frequencies along vibrational directionsDisplacements along the 3N-6 vibrational directions with Richardson extrapolation, spread over worker processes on the macOS build (Linux stays Partial). Checked against the analytic route: for water (Hartree-Fock, 6-31G) the finite-difference frequencies agree with the analytic ones within 0.005 cm-1 and the infrared intensities within 0.01 km/mol. No self-test compares this route with the all-Cartesian one or exercises the worker pool. Measured once at the 1.9.8 release, not a test: the nine M06-2X frequencies of trans-HCOOH moved by at most 0.0064 cm-1 against the all-Cartesian route of engine 1.9.7 with 6-311++G(d,p) on the SuperFine grid, and by 0.0096 cm-1 with 6-31G* on the Normal grid. Windows runs the displacements one after another: the measured Windows worker pool was slower, so it is off by default. Symmetry-unique displacements are not built. | Quantum Chemistry | Partial | 1.9.8 | |
| Density fitting RI-J, RI-JK, RI-MP2Resolution of the identity for Coulomb, exchange and MP2. RI-J with the built-in def2-universal-J set: the error per atom stays within the maxima printed in Weigend 2006 Table 2 (water, ammonia, hydrogen chloride). RI-JK and RI-MP2 with a generated auxiliary basis agree with the conventional energies within 1e-4 Eh for water. No printed RI energy is reproduced yet. | Quantum Chemistry | Partial | 0.7.17 | Weigend 2006; Weigend, Haser 1997 |
| Analytic Hessians (HF and DFT)Analytic HF and Kohn-Sham Hessians and dipole derivatives for LDA, GGA and global hybrids. | Quantum Chemistry | Partial | 0.7.65 | Pople et al. 1979; Johnson, Frisch 1994 |
| Wavefunction stabilityChecks and follows SCF instabilities for RHF, UHF, RKS and UKS. Not offered for meta-GGAs, wB97X-V, wB97M-V or double hybrids; the engine refuses with the reason. | Quantum Chemistry | Checked | 0.6 | Seeger, Pople 1977; Bauernschmitt, Ahlrichs 1996 |
| Point-group symmetry and orbital irrepsOpt-in point-group detection and symmetry use in the SCF, a symmetry tool (point group, equivalent atoms, symmetry number, operations), character tables for C3v, C5v, D3, D3h, D3d, D5, D5h, D5d, D2d, Td, Oh and the Abelian groups, linear groups C_inf_v and D_inf_h as families up to Lambda 6, and Hartree-Fock orbital irrep labels. Built, unchecked: character tables not yet compared with a printed table. Full-group tables for C4v, D4, D4h, C6v, D6h, T, Th, I, Ih and higher Cn, S2n, Dnd keep Abelian-subgroup labels. Orbital labels from Hartree-Fock only. | Quantum Chemistry | Partial | 0.7.40 | NIST CCCBDB point groups; Cotton 1990; Beruski, Vidal 2014 |
| Population analysis (Mulliken, Lowdin, Mayer, Hirshfeld, CM5, ESP, RESP)Atomic charges, bond orders, electrostatic potential fits and RESP. ESP and RESP from Hartree-Fock densities. | Quantum Chemistry | Partial | 0.7.16 | Mayer 1983; Hirshfeld 1977; Marenich et al. 2012; Bayly et al. 1993 |
| NBO with second-order E(2)Natural population, natural bond orbitals and donor-acceptor energies, and in the 1.8.0 build hybrid directions (NHO), natural localized molecular orbitals (NLMO) and one-step deletion energies. NHO, NLMO and deletion energies are our own definitions, unverified against the NBO program; deletion is a one-step estimate without SCF relaxation. Three-centre bonds, d-block rules and correlated densities are not built. | Quantum Chemistry | Partial | 0.7.65 | Reed, Curtiss, Weinhold 1988; Lowdin 1950 |
| QTAIM, ELF, NCI and Bader volumesCritical points, electron localisation, noncovalent interaction plots and basin volumes. | Quantum Chemistry | Partial | 0.7.65 | Bader 1990; Becke, Edgecombe 1990; Johnson et al. 2010; Tang, Sanville, Henkelman 2009 |
| Energy decompositionHartree-Fock energy decomposition for two closed-shell fragments. SAPT0 is the separate method below. | Quantum Chemistry | Partial | 0.7.65 | Kitaura, Morokuma 1976 |
| Counterpoise correctionBoys-Bernardi counterpoise energies and counterpoise optimisation for 2 to 4 fragments. | Quantum Chemistry | Checked | 0.7.65 | Boys, Bernardi 1970 |
| Polarisability and hyperpolarisabilityStatic polarisability by CPHF or finite field and the first hyperpolarisability. | Quantum Chemistry | Partial | 0.8.5 | Kurtz, Stewart, Dieter 1990 |
| CIS, TDA and TDDFTSinglet and triplet excitations, oscillator strengths, UV-Vis and ECD spectra. Printed-value check covers CIS excitation energies only (Foresman et al. 1992 Table I: formaldehyde, 32 energies in the STO-3G, 6-31G and 6-31G* columns). TDA and TDDFT energies, oscillator strengths and ECD are checked by exact identities and independent routes (explicit matrices, the polarisability sum rule, size consistency), not against printed values. | Excited States and Spectroscopy | Checked | 0.7.65 | Foresman et al. 1992; Hirata, Head-Gordon 1999; Casida 1995 |
| Natural transition orbitals and difference densitiesNatural transition orbital pairs with hole and particle orbitals, unrelaxed difference density, attached and detached electron densities and the unrelaxed excited-state dipole moment, for CIS, TDA, TDHF, TDDFT and spin-flip TDA states. Unrelaxed densities only; not offered for EOM-CCSD, CC2 or ADC(2) states. No printed orbital analysis reproduced yet. | Excited States and Spectroscopy | Partial | 1.5.0 | |
| EOM-CCSDCorrelated excitation energies and strengths on RHF references; CH+ reproduced from Stanton and Bartlett 1993. | Excited States and Spectroscopy | Checked | 0.9.0 | Stanton, Bartlett 1993 |
| ADC(2)Second-order algebraic diagrammatic construction excitation energies and strengths on RHF references. Checked by exact-property tests only; no printed excitation energy reproduced yet. | Excited States and Spectroscopy | Unverified | 0.9.0 | Schirmer 1982 |
| RI-CC2, SCS-CC2 and SOS-CC2Singlet and triplet vertical excitations on a closed-shell Hartree-Fock reference, with doubles never stored. Closed-shell RHF only; no transition moments, gradients or solvent; SOS-CC2 has no printed check. | Excited States and Spectroscopy | Partial | 1.10.0 | Hattig, Weigend 2000; Hellweg, Grun, Hattig 2008 |
| Excited states in solventCIS, TDA, TDHF and TDDFT energies and gradients in IEF-PCM or COSMO, equilibrium linear response. No nonequilibrium or state-specific schemes. | Excited States and Spectroscopy | Partial | 1.10.0 | Tomasi, Mennucci, Cammi 2005 |
| Correlation function rates (TVCF)Golden-rule internal conversion and intersystem crossing between two harmonic states with Duschinsky rotation, plus the spin-orbit coupling derivative. Checked at formula level against Englman and Jortner 1970 and against sum over states; no published rate reproduced yet. | Excited States and Spectroscopy | Partial | 1.10.0 | Peng et al. 2007; Niu et al. 2010; Peng et al. 2013; Englman, Jortner 1970 |
| Nonadiabatic couplings (Send-Furche)Ground to excited state derivative couplings from TDHF, TDDFT or TDA linear response, closed and open shell; guided form in Engine tools. Coupling to the ground state only. Printed-value check: the hydrogen-atom TDHF coupling against the exact value in Send, Furche 2010 Table III. Kohn-Sham couplings (PBE, PBE0) are checked against numerical orbital response only; no printed Kohn-Sham value is reproduced yet (the printed PBE0 hydrogen value needs the 10s8p basis from the paper's supplementary material, which is not held). | Excited States and Spectroscopy | Partial | 1.10.1 | Send, Furche 2010 |
| Excited-state gradientsCIS, TDA and TDDFT gradients for excited-state optimisation and emission. | Excited States and Spectroscopy | Partial | 0.7.53 | Furche, Ahlrichs 2002 |
| Core spectra (Delta-SCF, CVS)X-ray absorption by Delta-SCF and core-valence separation for K edges of Li to Ne, and the transition-potential method (half core hole, built in 1.8.0) that also reaches Na to Ar. Built, not tested numerically against a published table. Closed-shell references only. K edges only; L edges are not built. Nonrelativistic: no scalar-relativistic shift. | Excited States and Spectroscopy | Partial | 0.7.52 | Cederbaum, Domcke, Schirmer 1980; Besley, Gilbert, Gill 2009; Triguero, Pettersson, Agren 1998 |
| IR spectraHarmonic frequencies and intensities, scaled columns, broadened spectra. | Excited States and Spectroscopy | Checked | 0.6 | Wilson, Decius, Cross 1955 |
| Raman intensitiesRaman activities from polarisability derivatives. Hartree-Fock. | Excited States and Spectroscopy | Partial | 0.7.65 | Porezag, Pederson 1996 |
| VPT2 anharmonic frequenciesAnharmonic constants and fundamentals with variational Fermi resonance treatment. No states of three or more quanta. | Excited States and Spectroscopy | Checked | 1.2.0 | Barone 2005; Martin et al. 1995; Clabo et al. 1988 |
| NMR shielding (GIAO)Shielding tensors and chemical shifts for HF, LDA, GGA and global hybrids. Printed-value check is GIAO Hartree-Fock only (Wolinski, Hinton, Pulay 1990 Tables I and V: methane and benzene, with the geometry set by the printed SCF energy because the paper prints none). DFT shieldings are checked against finite-field Kohn-Sham calculations and the published functional ordering, not against printed numbers. | Excited States and Spectroscopy | Checked | 0.7.65 | Wolinski, Hinton, Pulay 1990 |
| NMR spin-spin couplingsFermi contact, spin-dipole, PSO and DSO terms. Fermi contact and spin-dipole terms are checked against finite-field calculations, all terms by exact symmetry identities, and the nuclear g factors against Stone 2005 Table 1. No printed coupling constant is reproduced yet. | Excited States and Spectroscopy | Partial | 1.0.0 | Ramsey 1953; Helgaker et al. 2000 |
| EPR hyperfine and g-tensorHyperfine tensors and the g-tensor for UHF and UKS. Hyperfine printed-value check is UHF only (methyl radical, Szabo and Ostlund 1996 Table 3.26); UKS hyperfine couplings are checked by identities only. Two hydrogen-atom comparisons with the measured 1420 MHz hyperfine frequency stay pending: the source of that value is not held. The g-tensor check is listed under EPR g-tensor in Relativistic and Magnetic. | Excited States and Spectroscopy | Checked | 0.7.54 | Neese 2001; Szabo, Ostlund 1996 |
| VCD spectraRotational strengths with GIAO atomic axial tensors, analytic for RHF and RKS. | Excited States and Spectroscopy | Partial | 1.0.0 | Stephens 1985; Cheeseman et al. 1996 |
| Raman optical activityStatic-limit ROA invariants with coupled Hartree-Fock. Frequency-dependent and Kohn-Sham ROA are not offered. | Excited States and Spectroscopy | Partial | 1.2.0 | Polavarapu 1990 |
| Surface hopping (FSSH)Fewest-switches surface hopping on CIS or TDA singlets and model problems. No hops into S0, no decoherence correction. | Excited States and Spectroscopy | Partial | 1.2.0 | Tully 1990; Hammes-Schiffer, Tully 1994 |
| Geometry optimisation with constraintsBFGS with trust radius, bond, angle and dihedral constraints. | Thermochemistry and Kinetics | Checked | 0.1 | Baker 1986 |
| RRHO thermochemistryZPE, H, S, G and Cp from harmonic frequencies. | Thermochemistry and Kinetics | Checked | 0.7.40 | McQuarrie 1976; Fernandez-Ramos et al. 2007 |
| Quasi-RRHO and hindered rotorsLow-mode entropy corrections, hindered rotors and standard state shifts. | Thermochemistry and Kinetics | Partial | 0.8.0 | Grimme 2012; Ribeiro et al. 2011 |
| Transition-state search (P-RFO)Partitioned rational function optimisation with Bofill updates. | Thermochemistry and Kinetics | Checked | 0.7.40 | Baker 1986; Bofill 1994; Baker, Chan 1996 |
| IRCGonzalez-Schlegel reaction path in mass-weighted coordinates. | Thermochemistry and Kinetics | Checked | 0.7.40 | Gonzalez, Schlegel 1989 |
| Climbing-image NEBMinimum energy paths with the improved tangent. | Thermochemistry and Kinetics | Partial | 0.7.45 | Henkelman, Uberuaga, Jonsson 2000 |
| Rigid and relaxed scansRigid scans along a bond, and relaxed scans along a bond, angle or dihedral with a constrained optimisation at every point (1 to 200 points), written as an energy profile and a trajectory. Rigid scans move one bond only; every angle and dihedral scan is relaxed. MMFF94 torsion barriers reproduce Halgren and Nachbar 1996 Table V (30 barriers, largest difference 0.0054 kcal/mol). | Thermochemistry and Kinetics | Checked | 0.1 | Halgren, Nachbar 1996 |
| TST rate constants with tunnellingConventional TST with Wigner or Skodje-Truhlar tunnelling. | Thermochemistry and Kinetics | Checked | 0.7.40 | Eyring 1935; Skodje, Truhlar 1981 |
| Variational TST with ZCT and SCTCanonical variational TST along the IRC with zero- and small-curvature tunnelling. Checked by exact identities and limits of the source papers only (projection of the path direction, a variational rate never above the conventional one, the zero-temperature limit, small-curvature equal to zero-curvature tunnelling on a straight path, the parabolic-barrier closed form of Skodje, Truhlar, Garrett 1981). No printed variational rate or tunnelling factor is reproduced yet. Large-curvature tunnelling refused. | Thermochemistry and Kinetics | Partial | 0.9.5 | Truhlar, Garrett 1984; Liu et al. 1993 |
| RRKM, Troe fall-off and master equationk(E), thermal fall-off curves and a master equation kernel. | Thermochemistry and Kinetics | Partial | 0.7.55 | Robinson, Holbrook 1972; Troe 1983; Miller, Klippenstein 2006 |
| Complete basis set extrapolationSCF and correlation energy extrapolation from cardinal series. | Thermochemistry and Kinetics | Partial | 0.7.60 | Helgaker et al. 1997; Halkier et al. 1998 |
| G3, G3X and G4 composite stepsStep plans, atomic energies and supplied-energy assembly for G3, G3X and G4. A full molecular G4 run is not claimed. | Thermochemistry and Kinetics | Partial | 1.2.0 | Curtiss et al. 2007; Curtiss et al. 1998; Curtiss et al. 2001 |
| G3 full runRunnable G3 steps 1 to 7 for H, C, N, O and F, assembled into the G3 energy (Unchecked). G4 E0 still refused. | Thermochemistry and Kinetics | Partial | 1.3.0 | Curtiss et al. 1998 |
| MMFF94Complete MMFF94 energies, minimisation, conformers, strain and frequencies. | Molecular Mechanics and Dynamics | Checked | 0.3 | Halgren 1996 |
| UFFUniversal force field across the periodic table. | Molecular Mechanics and Dynamics | Partial | 0.3 | Rappe et al. 1992 |
| AMBER Cornell 1995 and ff14SB compositeBiomolecular energies, optimisation, scans and MD. Parameters are those of Cornell et al. 1995 Table 14 (row counts and spot values compared with the printed table); energies and forces are checked by finite differences and invariance on N-methylacetamide with test charges. No printed energy or geometry is reproduced yet. The ff14SB option is a composite (Cornell 1995 base with the side-chain and psi terms of the Maier et al. 2015 Supporting Information), not the distributed ff14SB, and has no printed check. Missing parameters are refused, never invented. | Molecular Mechanics and Dynamics | Partial | 0.9.5 | Cornell et al. 1995; Maier et al. 2015 |
| CHARMM22 and CGenFFCHARMM functional form with residue typing from RTF records. CMAP is listed separately below. | Molecular Mechanics and Dynamics | Partial | 1.1.0 | MacKerell et al. 1998; Vanommeslaeghe et al. 2010 |
| Molecular dynamics (NVE, Nose-Hoover, Langevin)Lennard-Jones, MM, Born-Oppenheimer and MLP dynamics with exact restarts. Printed-value check covers the Lennard-Jones liquid only (Verlet 1967 Table I): the internal energy per atom at four state points within 0.02 and beta P/rho at five within 0.10, from Nose-Hoover chain runs of 256 or 864 atoms where Verlet ran 864 atoms at constant energy. The printed internal energy at density 0.88 and temperature 1.095 (-5.66) is not reproduced (ours -5.87). Thermostats are checked against exact canonical moments, and molecular mechanics, Born-Oppenheimer and MLP dynamics by energy conservation, time reversal and step-size scaling, not against printed values. Up to 600 atoms for MM in the isolated-molecule module, 5000 with the biomolecular force fields and 20000 for Lennard-Jones. | Molecular Mechanics and Dynamics | Checked | 0.7.40 | Martyna, Klein, Tuckerman 1992; Leimkuhler, Matthews 2013; Verlet 1967 |
| Born-Oppenheimer molecular dynamicsAb initio molecular dynamics on analytic Hartree-Fock or DFT gradients in NVE, Nose-Hoover chain, Langevin and Bussi ensembles, and metadynamics on ab initio forces. Up to 30 atoms and 20000 steps. No Car-Parrinello or extended-Lagrangian dynamics, and no NPT for isolated molecules. | Molecular Mechanics and Dynamics | Partial | 1.9.0 | |
| Periodic MD with Ewald and PMENVE, NVT and NPT boxes of TIP3P, SPC, SPC/E, TIP4P-Ew, TIP4P/2005 and OPC water. Printed-value checks: the Ewald sum reproduces the Wigner lattice constant 2.837297 (Yeh, Hummer 2004 Eq. 12) to six decimals; a Lennard-Jones NPT run at the pressure of the Verlet 1967 Table I state point (density 0.85, temperature 0.88) returns the density 0.849; the monomer dipole moments of SPC, SPC/E, TIP3P and OPC and the dipole and quadrupole moments of TIP4P-Ew and TIP4P/2005 equal the printed values. Liquid water: short NPT runs (216 molecules, PME, 12 ps) give 1.000 g/cm3 for SPC/E and 0.980 for TIP3P against the printed simulation values 0.998 and 0.982, which were obtained with plain cut-offs; this comparison is not like for like and is still marked pending. PME is checked against the Ewald sum, not against print, and no liquid property is reproduced for SPC, TIP4P-Ew, TIP4P/2005 or OPC. Triclinic cells are listed separately below. | Molecular Mechanics and Dynamics | Partial | 0.8.0 | Essmann et al. 1995; Miyamoto, Kollman 1992; Horn et al. 2004 |
| Conformer searchSystematic and stochastic conformers with MMFF94 ranking. MMFF94 conformer energies reproduce printed values; ring flips are not sampled. | Molecular Mechanics and Dynamics | Checked | 0.3 | |
| QM/MM (additive and subtractive)HF, DFT or MP2 regions in MMFF94 with electrostatic embedding and link atoms. No paper prints a value for QM/MM with this force field. Checked against exact properties: the gradient of the embedded QM energy, on the QM atoms and on the MM charges, equals finite differences of the energy within 1e-7 Eh/bohr for Hartree-Fock (closed and open shell) and MP2 regions and within 1e-6 for a PBE region; the complete QM/MM gradient with a link atom and the MMFF94 terms equals finite differences within 3e-7 kcal/mol/A for a Hartree-Fock region in six combinations of additive or subtractive scheme, electrostatic or mechanical embedding and three boundary-charge schemes, and has no net force or torque; a QM region equal to the whole system returns the plain QM energy and gradient; a distant chloride ion in the MM region reproduces the all-QM interaction energy with water within 1e-6 kcal/mol in a minimal basis. Not checked: hybrid functionals and large basis sets inside the QM region, DFT and MP2 regions together with link atoms, and regions near the 60 atom limit. Up to 60 QM atoms. | QM/MM and Free Energy | Checked (exact) | 0.7.45 | Warshel, Levitt 1976; Senn, Thiel 2009 |
| Umbrella sampling with WHAMPotentials of mean force along distances, angles and dihedrals. Runs on MMFF94, Lennard-Jones and model systems (up to 200 MM atoms). QM/MM umbrella sampling is not offered. | QM/MM and Free Energy | Partial | 0.7.45 | Torrie, Valleau 1977; Kumar et al. 1992 |
| Alchemical free energy (TI, FEP, BAR, MBAR)Free energy differences with blocking and bootstrap errors. | QM/MM and Free Energy | Partial | 0.7.45 | Zwanzig 1954; Bennett 1976; Shirts, Chodera 2008 |
| Metadynamics and replica exchangeStandard and well-tempered metadynamics, temperature replica exchange. | QM/MM and Free Energy | Partial | 0.7.45 | Laio, Parrinello 2002; Sugita, Okamoto 1999 |
| IEF-PCMContinuous surface charge PCM for energies, gradients and frequencies. | Solvation | Partial | 0.7.30 | Cances, Mennucci, Tomasi 1997; Scalmani, Frisch 2010 |
| COSMOConductor-like screening with segments for COSMO-RS. Equations follow Klamt et al. 1998; Klamt, Schuurmann 1993 is the original formalism. Checked against IEF-PCM and exact conductor results; no printed molecular COSMO energy is reproduced yet. | Solvation | Partial | 0.9.5 | Klamt et al. 1998; Klamt, Schuurmann 1993 |
| SMD (water)SMD cavity-dispersion-solvent structure term in water. Water only. The parameter tables (Marenich, Cramer, Truhlar 2009 Tables 3 to 5 and Supporting Information Part III) were read twice with identical results but are still flagged unverified by the engine. The term is checked against independent evaluations of the printed formulas, exact sphere and cap areas (within 1.5 %) and finite-difference gradients. No printed energy is reproduced: the paper prints error statistics, not values for single molecules. Organic solvents are listed separately below. | Solvation | Partial | 0.7.58 | Marenich, Cramer, Truhlar 2009 |
| Nonpolar solvationSwitched solvent-accessible area, surface tension and cavitation with gradients. Areas are checked against exact sphere and spherical-cap areas (within 1 %), gradients against finite differences, and the cavitation term against exact limits of the Pierotti formula as printed in Tomasi et al. 2005 (Eqs. 81, 82, 86). No printed cavitation or surface energy is reproduced yet. | Solvation | Partial | 0.7.56 | York, Karplus 1999; Tomasi et al. 2005 |
| COSMO-RSSigma profiles and potentials, activity coefficients, solvation free energies, vapour pressures and partition coefficients from COSMO segments; binary vapour-liquid and liquid-liquid equilibria and solid solubility. H, C, N, O and Cl, neutral compounds only. COSMO-RS parametrisation level not reproduced. A COSMO-SAC model core (Mullins et al. 2006) is built and checked on exact properties but not wired to the tool; no printed activity coefficient reproduced. | Solvation | Partial | 0.9.5 | Klamt 1995; Klamt, Eckert 2000; Mullins et al. 2006 |
| pKa from thermodynamic cyclesAbsolute and relative pKa with stated uncertainty. | Solvation | Partial | 0.7.56 | Kelly, Cramer, Truhlar 2006 |
| Redox potentialsStandard reduction potentials versus SHE or a reference couple. Printed-value check: from the printed proton solvation and formation free energies, Eq. (18), the tool reproduces the four absolute potentials of the standard hydrogen electrode in Marenich et al. 2014 Table 2 within 0.01 V. The calculated reduction potentials of Table 3 are not reproduced: only the 0.14 V shift between the 4.28 V and 4.42 V references is tested. Electron convention Unverified. | Solvation | Partial | 1.2.0 | Kelly, Cramer, Truhlar 2006; Marenich et al. 2014 |
| Cluster-continuum solvation of ionsCluster-continuum scheme for the solvation free energy and pKa of ions from explicit water clusters plus a continuum, composed from your own energy, thermochemistry and solvation results. You compose the energy calls; the tool combines them. No printed value reproduced yet. | Solvation | Partial | 1.9.0 | Ho, Coote 2010 |
| ElectrochemistryHydrogen electrode free energy steps against potential and pH, Pourbaix diagrams from couples with pKa values, and grand canonical electrode energies. Hydrogen-electrode steps, Pourbaix lines and grand canonical electrode energies are checked by exact algebra only; the source paper of the computational hydrogen electrode (Norskov et al. 2004) is not held. The comparison with Marenich et al. 2014 belongs to the redox-potential tool: it reproduces the absolute hydrogen-electrode potentials of Table 2 from the printed proton free energies within 0.01 V, not the calculated potentials of Table 3. No printed electrode potential is reproduced by this tool. No implicit electrolyte for periodic electrodes and no constant-potential SCF. | Solvation | Partial | 1.9.0 | Marenich et al. 2014 |
| Spin-free X2CExact two-component one-electron Hamiltonian for energies and orbitals. | Relativistic and Magnetic | Checked | 0.9.0 | Kutzelnigg, Liu 2005; Ilias, Saue 2007; Reiher 2006 |
| Scalar ZORAZeroth-order regular approximation by numerical quadrature. | Relativistic and Magnetic | Unverified | 0.9.0 | van Lenthe, Snijders, Baerends 1996 |
| Effective core potentialsStuttgart sets for Ag, Cd, Au, Hg and Ga, Ge, As, In, Sn, Sb, Pb, Bi, and Wadt-Hay sets for Na to Ar. Energy and orbitals only: no ECP gradients, correlated methods or solvation. Printed-value checks: Hartree-Fock ionisation energies of Ag, Cd, Au and Hg agree with Andrae et al. 1990 Table 3 within 0.02 eV (valence basis of the paper; open-shell states unrestricted), and the valence energies of Na, Mg and Ar with Wadt, Hay 1985 Table XVII within 2e-5 Eh. For Al to Cl our unrestricted energies lie at or below the printed values by less than 0.002 Eh, because the open-shell treatment of the paper is not reproduced. The Metz, Stoll, Dolg 2000 sets for Ga, Ge, As, In, Sn, Sb, Pb and Bi are unverified: only the Pb parameters were compared with the printed table; no printed energy is reproduced yet. | Relativistic and Magnetic | Partial | 0.9.0 | Andrae et al. 1990; Metz, Stoll, Dolg 2000; Wadt, Hay 1985 |
| Spin-orbit couplingSinglet-triplet couplings from CIS/TDA or full-response TDHF/TDDFT amplitudes, with the one-electron effective-charge or the mean-field operator, and atomic fine structure. The effective nuclear charges equal those printed in Neese 2001 and Koseki et al. 1995, 1998; spin-orbit integrals are checked against numerical quadrature, state couplings against explicit Slater determinants, and atomic multiplets against exact splitting rules. One printed value is matched: the Cu(II) spin-orbit constant, 848 cm-1 against 845 (Neese 2001 Table VI, with different orbitals). No printed singlet-triplet coupling or fine-structure splitting is reproduced yet. Closed-shell references for state couplings; no solvent, range-separated hybrids, meta-GGA or ECP; no spin-orbit perturbed energies. | Relativistic and Magnetic | Partial | 1.2.2 | Koseki et al. 1995; Koseki et al. 1998; Neese 2001; Hess et al. 1996; de Souza et al. 2019 |
| Mean-field two-electron SOCMean-field one- plus two-electron spin-orbit operator (one-centre or all integrals) for the g-tensor and singlet-triplet couplings. Printed-value checks go through the zero-field splitting and the g-tensor, not through state couplings. All-integral form: the spin-orbit part of the O2 zero-field splitting is 1.62 cm-1 against 1.60 (Neese 2007 Table I, BLYP/def2-TZVPP, bond length 1.2075 A because the paper prints no geometry). One-centre form: for CO+ and H2O+ the two-electron spin-orbit contribution to the g-shift agrees with Malkina et al. 2000 Tables 1 and 2 within about 7 % and its ratio to the one-electron term within 0.02, with a different functional and basis (ours PBE/def2-TZVPP, the paper BP86 with basis BIII): that part is a pattern, not a match. The two large components of the H2O+ g-shift are 9 and 14 % above the printed ones. Singlet-triplet couplings with this operator are compared only with the effective-charge operator, not with printed values. The all-integral form is limited to 150 basis functions. | Relativistic and Magnetic | Checked | 1.3.0 | Hess et al. 1996; Marian 2012; Neese 2007; Malkina et al. 2000 |
| EPR g-tensorRelativistic mass, gauge and spin-orbit contributions for UHF and UKS. Printed-value checks use UKS (PBE, PBE0). Relativistic mass and gauge corrections match printed values within 10 ppm for H2O+ (Lushington, Grein 1997 Table I at the printed geometry; Neese 2001 Table IV) and within 15 ppm for CO+ (Lushington, Grein 1997 Table I); the CO+ gauge correction of Neese 2001 Table III (138 and 30 ppm) is not reproduced (ours 194 and 81). Against Neese 2001 Table I the large components of the total Delta g agree only within about 15 %, with our own geometry and basis because that paper prints no geometries. | Relativistic and Magnetic | Checked | 1.2.2 | Neese 2001; Lushington, Grein 1997 |
| Neural network potentialsBehler-Parrinello potentials with ANI-type descriptors and analytic forces. Since 1.9.3 you can import your own extended-XYZ or JSON reference data; units, finite values, distances, forces, duplicates and energy outliers are checked and the data set is sealed. Trained only on your own data (engine-generated or imported by you); models stay in your organisation and are labelled trained on user-provided data. | Machine-Learned Potentials | Unverified | 0.9.0 | Behler, Parrinello 2007; Smith, Isayev, Roitberg 2017 |
| Force training, ensembles, active learningEnergy and force training, committee ensembles and uncertainty-driven sampling. | Machine-Learned Potentials | Partial | 1.1.0 | Smith et al. 2018 |
| MLP dynamics and optimisationUse a trained model in MD and geometry optimisation. | Machine-Learned Potentials | Partial | 0.9.0 | |
| Descriptors (logP, TPSA, Lipinski)Crippen logP, TPSA and rule-of-five properties. | Cheminformatics | Checked | 0.2 | Wildman, Crippen 1999; Ertl, Rohde, Selzer 2000; Lipinski et al. 1997 |
| Fingerprints, similarity, clusteringCircular fingerprints in the ECFP4 style (radius 2, 2048 bits), Tanimoto similarity and Butina clustering. Not the published ECFP_4: the fingerprint keeps an identifier for every atom at every iteration and has no duplicate-substructure removal, so it does not reproduce the identifier counts of Rogers, Hahn 2010 Figure 8 (17 against the printed 14 at diameter 4 for butyramide) and its Tanimoto values can differ from those of the published algorithm. Checked by definition tests only: the same fingerprint for another atom order, a symmetric similarity inside its range, one clustering case. No printed Tanimoto value or clustering result is reproduced. | Cheminformatics | Partial | 0.2 | Rogers, Hahn 2010; Butina 1999 |
| Substructure searchSubstructure matching with Daylight SMARTS molecule patterns, including recursive $() and component grouping. Reaction queries are refused, and stereo in a pattern (chirality and bond direction) is parsed but ignored in matching. Checked against 137 hand-counted patterns (13 recursive, 14 component-grouped) and, for 60 pattern and molecule pairs, against exhaustive enumeration. The match examples printed in the SMARTS specification are not in the self-test yet. | Cheminformatics | Partial | 0.2 | |
| CIP stereodescriptorsR, S, r, s, E and Z by the IUPAC 2013 Sequence Rules. | Cheminformatics | Checked | 0.7.22 | IUPAC 2013 P-92 |
| IUPAC namesSystematic names for a growing set of structure classes. Printed-value check: for 285 structures drawn by hand from examples in the 2013 IUPAC recommendations the generated name equals the printed preferred IUPAC name (acids, alcohols, ketones, amines, rings and benzenes; esters, amides, acyl halides, lactones, lactams and heteromonocycles; 32 stereo examples of P-93). The stereodescriptors of the P-93 set were assigned with the engine's own CIP code, so they are not an independent check. Covered: neutral single-component molecules of C, H, N, O and halogens (sulfur in rings) in these classes; anything else is refused, never guessed. | Cheminformatics | Checked | 1.0.0 | IUPAC 2013 P-14 to P-44 |
| File formatsReads XYZ, MOL and SDF V2000 and V3000, PDB, PQR, GRO, CIF, mmCIF, CML, cube, Molden and JCAMP-DX; writes XYZ, MOL and SDF, PDB, PQR, GRO, cube, Molden and JCAMP-DX; SMILES in both directions. CIF, mmCIF and CML are read only. Molden normalisation and CIF orthogonalisation are Unverified. Mol2, FCHK and InChI writing are not built (InChI is read: see the InChI row). | Cheminformatics | Checked | 0.7.25 | wwPDB v3.30; Hall, Allen, Brown 1991; Dalby et al. 1992; McDonald, Wilks 1988 |
| Model systems (grid, tunnelling, wavepackets)Exact-answer quantum models for teaching and checks. Checked against exact closed forms only: particle-in-a-box, harmonic, Morse and hydrogen radial levels within a relative error of 1e-8, the Eckart transmission from a transfer matrix against its closed form within 1e-6, and wavepacket propagation by its conserved norm and the harmonic levels in its spectrum. No printed value is reproduced yet, although two source papers print tables: the tunnelling corrections of Johnston, Heicklen 1962 (Table I) and the double-well eigenvalues of Feit, Fleck, Steiger 1982 (Table I) are not in the self-test. Anharmonic levels from a bond scan are checked for grid convergence only. | Quantum Chemistry | Partial | 0.4 | Feit, Fleck, Steiger 1982; Morse 1929; Eckart 1930; Johnston, Heicklen 1962 |
| Distributed SCFOne SCF split over up to 64 ranks with bitwise reproducible sums. No paper prints a value for this. Checked by recomputation: the energy of one SCF split over 2 and 3 ranks equals the energy of the same SCF on one rank within 1e-10 Eh (Hartree-Fock, closed and open shell), repeated runs with the same rank count are identical bit for bit, and the Coulomb and exchange matrices built in pieces equal the serial ones within 1e-12 (within 1e-11 when built over three ranks). Not checked: more than 3 ranks in one run, Kohn-Sham runs, real network links (the test ranks exchange data in memory) and any speed-up. | HPC and Clusters | Checked (exact) | 0.7.24 | |
| Slurm, PBS and LSF submission (scheduler bridge)Jobs sent to your own scheduler through its head node, with job-state parsers for squeue, sacct, sinfo, qstat and bjobs. In build, not released: the parsers pass their own tests, but the bridge has not run on a real scheduler site and is not installed on the portal. | HPC and Clusters | In build, not released | 0.7.40 | |
| Rank-loss recovery, distributed MP2, SCF checkpointsSurvive a lost node, split MP2, resume from checkpoints. | HPC and Clusters | Partial | 1.3.0 | |
| Split frequencies over serversHessian rows computed in parts on several servers and merged. No paper prints a value for this. Checked by recomputation: the nine Hessian rows of water (Hartree-Fock, STO-3G) computed in three separate parts and merged give the same frequencies and infrared intensities as one run with the same Cartesian displacements, bit for bit. Not checked: parts computed on servers with different processors, which need not round identically. A single run by default displaces along the vibrational directions instead, so it differs from a split run in the fourth decimal of a wavenumber: 7e-4 cm-1 for water on one machine, 2.4e-4 cm-1 in one measured run split over two servers (engine 1.9.8). | HPC and Clusters | Checked (exact) | 0.7.40 | |
| SAPT0 interaction energiesElectrostatics, exchange, induction and dispersion with delta HF for two closed-shell fragments. Exchange-induction term Unverified; no density fitting. | Quantum Chemistry | Partial | 1.4.0 | Jeziorski, Bulski, Piela 1976; Rybak, Jeziorski, Szalewicz 1991; Hesselmann, Jansen, Schutz 2005; Hohenstein, Sherrill 2010 |
| Built-in D3 and D4 damping parametersD3(0) parameters for PBE, BLYP, PBE0, TPSS, HF, SCAN, M06, M06-2X, TPSSh and M06-L; D3(BJ) for PBE, BLYP, PBE0, TPSS, HF, SCAN and TPSSh; D4 for twelve functionals including CAM-B3LYP, wB97 and wB97X. Functionals outside these lists are not offered with this model. Double hybrids are refused with the reason. | Quantum Chemistry | Partial | 1.9.4 | Grimme et al. 2010; Grimme, Ehrlich, Goerigk 2011; Caldeweyher et al. 2019 |
| ROHF and RO-KSRestricted open-shell Hartree-Fock and Kohn-Sham energies. No ROHF gradients, Hessians or correlation on an ROHF reference. | Quantum Chemistry | Partial | 1.5.0 | |
| DLPNO-CCSD(T0) and CCSD(T)-F12Local pair natural orbital MP2 and CCSD(T0), and explicitly correlated MP2-F12 and CCSD(T)-F12a/b, closed shell. Not linear scaling yet; MP2-F12 parts pending source checks. | Quantum Chemistry | Partial | 1.5.0 | Riplinger, Neese 2013; Peterson, Adler, Werner 2008 |
| MS-CASPT2, XMS-CASPT2, ic-MRCISD+Q and DMRGMultistate perturbation theory, internally contracted MRCI with Davidson corrections, and DMRG as a CAS solver. No IPEA or imaginary shift; DMRG reaches CI sizes only. | Quantum Chemistry | Partial | 1.5.0 | Finley et al. 1998; Werner, Knowles 1988; Chan, Head-Gordon 2002 |
| ONIOM, COSX and low-scaling SCFTwo- to five-layer ONIOM with mechanical embedding (with gradient) or electronic embedding (energy only), COSX exchange and CFMM Coulomb. CFMM one tree level. Electronic embedding gives energies only. | Quantum Chemistry | Partial | 1.5.0 | Vreven et al. 2006 |
| Projection embedding and frozen-density embeddingDFT-in-DFT, HF-in-DFT and MP2-in-DFT projection embedding of chosen active atoms, and frozen-density embedding with freeze-and-thaw. Projection embedding: the embedded energy with the first-order correction equals the full Kohn-Sham energy to 1e-10 Eh at a level shift of 1e5 (Manby et al. 2012 Table 1, ethanol). At the shift of 1e3 used in the paper our error is 1e-6 Eh against the printed 7e-12, so the printed accuracy is not reproduced yet. Frozen-density embedding uses a Thomas-Fermi nonadditive kinetic term that is not checked against a printed value. Closed shell for the low level. | Quantum Chemistry | Partial | 1.5.0 | Manby et al. 2012 |
| iMTD conformer searchRMSD-biased metadynamics conformer search with unbiased MD, sorting and Boltzmann populations, at MMFF94 or UFF level. Genetic structure crossing is not built, and GFN2, DFTB3, PM6 and PM7 levels are refused for the search. | Quantum Chemistry | Partial | 1.5.0 | Pracht, Bohle, Grimme 2020 |
| VYROX Math KernelOur own dense linear algebra: packed GEMM, blocked Cholesky, LU and TRSM, and a threaded symmetric eigensolver, with no third-party math library. GEMM kernels for Apple SME and ARM NEON with a scalar fallback, and a blocked Householder tridiagonalisation followed by the QL algorithm. A single-thread GEMM is also used inside the meta-GGA grid code (since 1.9.8). Auto mode routes GEMM and the eigensolver only. One measured speed: dgemm 256x4096x4096 on 16 threads ran 1.13 to 1.20 times Intel MKL. On the other sizes we measured it ran slower than MKL, so no parity is claimed. | HPC and Clusters | Partial | 1.5.0 | Householder 1958; Bowdler et al. 1968; Cuppen 1981; Gu, Eisenstat 1995 |
| GPU J and K buildsDirect screened Coulomb and exchange on the GPU up to d functions, and GPU RI-J three-centre integrals, in CUDA builds. Off by default until measured faster than the CPU. | HPC and Clusters | Unverified | 1.5.0 | Ufimtsev, Martinez 2008; Ufimtsev, Martinez 2009; Haser, Ahlrichs 1989 |
| Plane-wave periodic DFTLDA, GGA and global hybrid functionals with norm-conserving GTH and HGH pseudopotentials, k-points with symmetry, forces, stress, relaxation, equation of state, band structures, DOS, spin polarisation, Born-Oppenheimer MD and Bader analysis. No PAW, ultrasoft or UPF files and no meta-GGA. Hybrids need the full k mesh and no smearing. | Quantum Chemistry | Unverified | 1.5.0 | Kohn, Sham 1965; Monkhorst, Pack 1976; Setyawan, Curtarolo 2010 |
| Spin-flip TDA, EOM-IP/EA-CCSD and CC2Spin-flip excitations from high-spin references, ionisation energies, electron affinities and CC2 excitations. No CC2 strengths or meta-GGA TDDFT kernel. RI-CC2 is its own row. | Excited States and Spectroscopy | Partial | 1.5.0 | Shao, Head-Gordon, Krylov 2003; Christiansen, Koch, Jorgensen 1995 |
| Vibronic spectra and anharmonic intensitiesVibrationally resolved absorption and emission spectra with Franck-Condon and Herzberg-Teller moments, Duschinsky rotation, adiabatic Hessian, vertical Hessian and vertical gradient models, time-independent and time-dependent (0 K) methods, Boltzmann initial states, resonance Raman A term, and VPT2 IR and Raman intensities. 3 to 200 atoms (3 to 40 when the initial state comes from a job). Variational GVPT2 intensities not built. Matches the closed Franck-Condon formulas of Sharp and Rosenstock 1964 to 1e-13; the paper prints figures only, so no printed spectrum is reproduced. | Excited States and Spectroscopy | Partial | 1.5.0 | Santoro et al. 2007; Bloino, Barone 2012; Sharp, Rosenstock 1964 |
| DKH2, SOMF spin-orbit and paramagnetic NMRSecond-order Douglas-Kroll-Hess, spin-orbit coupling with the mean-field operator and paramagnetic NMR shifts from the hyperfine and g tensors. No coupled-perturbed SOC for hybrids; paramagnetic NMR is built and not yet run, for doublets only and without orbital shielding of open shells. | Relativistic and Magnetic | Unverified | 1.5.0 | Reiher 2006; Neese 2007 |
| Zero-field splittingZero-field splitting D and E from the spin-spin and spin-orbit terms, with the mean-field spin-orbit operator and its variants, for UHF and UKS with multiplicity 3 or more; the D tensor is reported in its proper frame with the contributions. Spin-orbit D reproduces Neese 2007 Table I; spin-spin D from the UKS spin density differs from the printed UNO value (UNO not built). The spin-orbit part with exact exchange, meta-GGA, range-separated hybrids, ECPs, relativistic Hamiltonians, correlated methods and solvation are refused; spin-spin needs at most 150 basis functions. | Relativistic and Magnetic | Partial | 1.9.0 | Neese 2007 |
| Exchange coupling from broken symmetryHeisenberg exchange coupling J between two spin fragments from high-spin and broken-symmetry UHF or UKS determinants, by the Yamaguchi, Noodleman and Bencini formulas. Built and not yet run against a printed value. Two fragments only. | Relativistic and Magnetic | Unverified | 1.9.0 | Neese 2009 |
| Electric field gradients and MossbauerElectric field gradient tensors at the nuclei, nuclear quadrupole coupling constants, and 57Fe Mossbauer quadrupole splitting and isomer shift from the SCF electron density, with a published calibration or one you fit. Built and not yet run against a printed value. All-electron RHF, RKS, UHF and UKS densities only. | Relativistic and Magnetic | Unverified | 1.9.0 | Neese 2009; Helgaker et al. 1999 |
| Conformer ensembles, BDE and atomisation energiesBoltzmann ensemble free energies, bond dissociation energies, total atomisation energies and two-point CBS extrapolation. W1, W2, CBS-QB3 and full G4 refused: papers not held. | Thermochemistry and Kinetics | Partial | 1.5.0 | Pracht, Bohle, Grimme 2020; Karton, Daon, Martin 2011 |
| Microkinetic modelling and energetic spanStiff microkinetic models, degree of rate control, reaction networks, Curtin-Hammett, Arrhenius and Eyring fits, TOF and energetic span. | Thermochemistry and Kinetics | Partial | 1.4.0 | Kozuch, Shaik 2006; Kozuch, Shaik 2011; Campbell 2001 |
| Dimer method saddle searchTransition states without a Hessian by the dimer method. | Thermochemistry and Kinetics | Partial | 1.4.0 | Henkelman, Jonsson 1999 |
| GAFF, AM1-BCC and RESP ligand chargesGAFF atom typing, ligand charges and protein plus ligand plus TIP3P systems. Parameters not printed in the paper are refused unless you supply them. | Molecular Mechanics and Dynamics | Partial | 1.4.0 | Wang et al. 2004; Jakalian, Jack, Bayly 2002; Bayly et al. 1993 |
| QM-derived ligand parameters (Seminario)Bond and angle force constants from the QM Hessian, Seminario and modified Seminario. Fit corrections are engineering choices. | Molecular Mechanics and Dynamics | Unverified | 1.4.0 | Seminario 1996; Allen et al. 2018 |
| ff99SB family, a99SB-disp, OPLS-AA and OpenFFAMBER ff99SB, ff99SB-ILDN, ff99SB*-ILDN, a99SB-disp with its water, TIP4P-D, OPLS-AA, OPLS-AA/M and OpenFF Parsley 1.0.0 parameters. DES-Amber refused with the reason. The AMBER sets are checked against their source tables; OPLS-AA and OPLS-AA/M are built and unverified. | Molecular Mechanics and Dynamics | Partial | 1.6.0 | Hornak et al. 2006; Lindorff-Larsen et al. 2010; Robustelli, Piana, Shaw 2018; Jorgensen, Maxwell, Tirado-Rives 1996; Robertson, Tirado-Rives, Jorgensen 2015; Qiu et al. 2021 |
| GB screening sets and nonlinear Poisson-BoltzmannSRI99 screening as the default Generalized Born set, the HCT96 SM5.4PD pair set, and the nonlinear Poisson-Boltzmann total electrostatic energy. The Srinivasan et al. 1999 screening values (H, C, N, O, P, S, Fe) and the Hawkins, Cramer, Truhlar 1996 SM5.4PD radii and pair factors equal the printed tables; other elements are refused. The nonlinear Poisson-Boltzmann energy is checked against the linear energy in the low-salt limit and by sign rules (Sharp, Honig 1990), not against a printed value. No printed GB or PB energy is reproduced yet. | Solvation | Partial | 1.6.0 | |
| Smearing, DFT+U and DFPT phononsGaussian, Methfessel-Paxton, cold and tetrahedron smearing in plane-wave DFT, Liechtenstein DFT+U for d shells, DFPT phonons for insulators, and finite-displacement phonons with dispersion and thermodynamics. DFPT is spin-unpolarised and slow; no PAW. | Quantum Chemistry | Partial | 1.6.0 | Methfessel, Paxton 1989; Liechtenstein, Anisimov, Zaanen 1995 |
| Wannier functionsMaximally localised Wannier functions for an isolated band group in plane-wave DFT: projection on s, p and sp3 trial orbitals, spread minimisation, centres, spreads, the Hamiltonian in the Wannier basis and Wannier-interpolated bands. Isolated bands only; entangled bands (disentanglement) are not built. Silicon spread reproduces Marzari and Vanderbilt 1997 Table I (4x4x4 mesh, within 0.2%). | Quantum Chemistry | Checked | 1.9.0 | Marzari et al. 2012; Marzari, Vanderbilt 1997 |
| CCSD and CCSD(T) analytic gradientsAnalytic nuclear gradients of CCSD and CCSD(T) for RHF and UHF references with frozen core, for optimisation, transition states and frequencies by differences of gradients. Equations derived from the published formalism and checked against finite differences; no ROHF, density functional, solvation or local variants. | Quantum Chemistry | Partial | 1.6.0 | Watts, Gauss, Bartlett 1993; Scuseria 1991; Handy, Schaefer 1984 |
| Tkatchenko-Scheffler and many-body dispersionTS pairwise dispersion and MBD@rsSCS and MBD@TS many-body dispersion with analytic gradients. Parameters printed for PBE and PBE0; H, C, N and O radii only, other inputs are yours. | Quantum Chemistry | Partial | 1.6.0 | Tkatchenko, Scheffler 2009; Tkatchenko et al. 2012; Ambrosetti et al. 2014 |
| Make 3D for hard structuresMore embedding attempts, a four-dimensional embedding and relaxed bounds, then force-field clean-up, with radii for elements 1 to 86, so cages, fused rings and salts get a 3D structure; a refusal names the atoms and bonds at fault. Bonded metals are refused by name: no coordination-geometry model. | Cheminformatics | Partial | 1.6.0 | Pyykko, Atsumi 2009 |
| QM/MM response propertiesPolarizability, TDHF, TDA and TDDFT excitations and Raman of a QM region embedded in fixed MM point charges. Tested only with the embedding charge set to zero, by three identities: the polarizability equals that of the plain polarizability tool within 2e-5 a.u. (water, Hartree-Fock, 6-31G*), and the Raman frequencies and activities equal those of the plain Raman tool within 0.5 cm-1 and 0.5 percent (water, Hartree-Fock, STO-3G). Nothing is tested with non-zero charges, and the excitation energies have no test. Fixed charges, no MM polarisation, no boundary treatment inside the tool, HF and Kohn-Sham only, at most 10 QM atoms for Raman. | QM/MM and Free Energy | Partial | 1.8.0 | Senn, Thiel 2009; Porezag, Pederson 1996 |
| Automatic auxiliary basis generatorGenerates an even-tempered auxiliary set from the orbital basis for RI-JK and RI-MP2. An auto-generator, not a published set: accuracy against an RI error budget is not checked; angular momentum capped at g; Z up to 36. Selectable as autoaux, autoaux-jk or autoaux-mp2; the built set is registered with its SHA-256. | Quantum Chemistry | Partial | 1.8.0 | Weigend 2007; Hattig 2005 |
| DFT Raman and finite-field hyperpolarizabilityRaman intensities from a Kohn-Sham Hessian and finite-field polarizabilities, and the first hyperpolarizability by finite field with Richardson extrapolation. Built, not tested numerically. Meta-GGA, VV10, range-separated and double hybrids refused; at most 20 atoms. | Excited States and Spectroscopy | Partial | 1.7.0 | Porezag, Pederson 1996 |
| CHARMM22 CMAP and OPC waterCMAP backbone correction and the OPC four-site water model. CHARMM36 and ff19SB refused: parameter files not held. | Molecular Mechanics and Dynamics | Partial | 1.5.0 | MacKerell, Feig, Brooks 2004; Izadi, Anandakrishnan, Onufriev 2014 |
| Bussi thermostat, MTTK and Parrinello-Rahman barostats, r-RESPAStochastic velocity rescaling, MTTK and Parrinello-Rahman pressure coupling, multiple time step dynamics. No barostat with constraints. | Molecular Mechanics and Dynamics | Partial | 1.4.0 | Bussi, Donadio, Parrinello 2007; Martyna et al. 1996; Parrinello, Rahman 1981; Tuckerman, Berne, Martyna 1992 |
| Triclinic cells, LINCS and hydrogen mass repartitioningTriclinic water, Lennard-Jones and MM cells with PME, anisotropic and flexible NPT, LINCS constraints. Triclinic Lennard-Jones and MM cells and anisotropic or flexible NPT came with 1.5.0. Anisotropic MTTK reduction Unverified. | Molecular Mechanics and Dynamics | Partial | 1.4.0 | Hess et al. 1997; Essmann et al. 1995 |
| Steered MD, Jarzynski and trajectory analysisSteered MD with Jarzynski and Crooks work estimators, RDF, MSD, VACF, RMSD and H-bond analysis. No paper prints a value for the work estimators. Checked against exact properties: the Jarzynski and Crooks free energies of a pulled harmonic particle and of a distance pull agree with the exact free energy differences within 0.2 kT (400 trajectories); neighbour-list energies, forces and virials equal the all-pairs sums within a relative 1e-11; the radial distribution function of an ideal gas, mean-square displacement, velocity autocorrelation, superposition RMSD and hydrogen-bond lifetimes are checked on cases with known answers. Printed-value side check: the Lennard-Jones liquid energy and pressure from the radial distribution function agree with Verlet 1967 Table I within 0.02 and 0.07. Not checked: steered runs on molecular force fields beyond finishing with a finite estimate; no printed potential of mean force is reproduced. | Molecular Mechanics and Dynamics | Checked (exact) | 1.4.0 | Jarzynski 1997; Shirts et al. 2003; Yeh, Hummer 2004; Verlet 1967 |
| Generalized Born, MM/GBSA and Poisson-BoltzmannHCT, OBC1 and OBC2 Generalized Born with decomposition, MM/GBSA, and linear and nonlinear finite-difference Poisson-Boltzmann potentials. GB energies are checked against the Born formula for one ion and the Still pair formula, the HCT closed form against direct quadrature, and Poisson-Boltzmann potentials against the Born ion and the analytic sphere solutions of Tironi et al. 1995 (within 2 %); MM/GBSA by exact sum rules. No printed GB, PB or MM/GBSA energy of a molecule is reproduced yet. GBn2 and PB forces refused. | Solvation | Partial | 1.4.0 | Onufriev, Bashford, Case 2004; Kollman et al. 2000 |
| SMD in organic solvents and 3D-RISMSMD with solvent descriptors you supply, and 3D-RISM solvent distributions with HNC closure. No built-in organic descriptors. 3D-RISM gives solvent distributions only, no solvation free energy. | Solvation | Partial | 1.5.0 | Marenich, Cramer, Truhlar 2009 |
| ABF, REST2, GaMD, OPES and multiple walkersAdaptive biasing force, replica exchange with solute tempering, Gaussian accelerated MD and OPES. REST2 on model systems only. | QM/MM and Free Energy | Partial | 1.5.0 | Wang, Friesner, Berne 2011; Miao, Feher, McCammon 2015; Invernizzi, Parrinello 2020 |
| End-point binding energy (MM/GBSA and MM/PBSA)Binding free energy of a complex from MM/GBSA and MM/PBSA end-point calculations on snapshots, with per-term decomposition. The entropy term is not computed. HCT scale factors must be supplied; GBn2 and Poisson-Boltzmann forces are refused. No distributed program value reproduced. | QM/MM and Free Energy | Partial | 1.4.0 | Kollman et al. 2000; Onufriev, Bashford, Case 2004 |
| Free energy cycle closureCycle closure of a relative free energy map: node free energies, corrected edges and hysteresis per loop from FEP, TI or BAR edge values with their uncertainties. Works on edge values you supply or computed elsewhere in the Lab; it does not compute the edges. | QM/MM and Free Energy | Partial | 1.9.0 | Wang et al. 2013 |
| Constant-pH titrationDiscrete-protonation Monte Carlo titration of point-charge sites with reference pKa values, giving an apparent pKa per site. The six built-in reference pKa values are those of Mongan, Case, McCammon 2004 Table 1; an isolated site titrates on the Henderson-Hasselbalch curve at its reference pKa, which is an identity of the method. Interacting sites are checked for the sign of the shift only. No printed titration result is reproduced: the lysozyme values of that paper need constant-pH molecular dynamics in generalised Born solvent, which is not built. Not coupled to molecular dynamics. | QM/MM and Free Energy | Partial | 1.9.0 | Mongan, Case, McCammon 2004 |
| SchNet, NequIP-style, Deep Potential and GAPMessage-passing, equivariant, local-frame and SOAP kernel potentials trained on your own engine data. Not periodic, no GPU training. | Machine-Learned Potentials | Unverified | 1.5.0 | Bartok, Csanyi 2015; Zhang et al. 2018 |
| Docking and drug-likenessLigand docking, scoring, virtual screening and RMSD, with LIGSITE pocket detection and drug-likeness rules. The Vina-form scoring terms and weights follow Trott, Olson 2010 (the six weights equal its Table 1; terms checked at chosen distances against the printed formulas). The search moves and RMSD are checked by exact geometric identities, pocket detection on a constructed cavity, and the solubility and absorption rules against their printed equations. No printed docking pose, score or pocket is reproduced, and scores are not calibrated against affinities. | Cheminformatics | Partial | 1.5.0 | Lipinski et al. 1997; Veber et al. 2002; Hendlich et al. 1997 |
| Pharmacophore, shape and drug-likeness filtersPharmacophore feature matching, hard-sphere shape similarity with principal-axes alignment, ESOL solubility, Egan, Lipinski and Veber rules, and a filter cascade before docking. Published rules and one solubility model only; no trained ADMET models. | Cheminformatics | Partial | 1.5.0 | Delaney 2004; Egan et al. 2000; Lipinski et al. 1997; Veber et al. 2002 |
| InChI reading and identity check, bridged-ring depictionReads InChI, checks a structure against an InChI, bridged and caged ring layout, wedge rules. Writing InChI and InChIKey refused: technical manual not held. | Cheminformatics | Partial | 1.5.0 | Fricker, Gastreich, Rarey 2004; Clark 2006; Brecher 2006 |
| Query structures and 2D depictionMOL V2000 and V3000 with S-groups, R-groups, atom lists, generic and query atoms, query bonds, link nodes, enhanced stereo and coordination bonds; 2D layout with wedge and hash bonds for bridged and caged rings. Prefabricated cage templates are not built. Writing InChI and InChIKey is refused. | Cheminformatics | Partial | 1.3.0 | Dalby et al. 1992; Fricker, Gastreich, Rarey 2004 |
| Molecular descriptors and gradient-boosted treesE-state atom-type and topological descriptors, then gradient-boosted tree models on your own data with k-fold cross-validation, grid search, permutation importance and Tree SHAP; guided forms in Engine tools. Printed-value checks cover the descriptors only: the electrotopological state values of the atoms of histidine equal Hall, Kier 1995 Table 2 for 10 of 11 atoms within 0.0006 (the amino nitrogen is 5.254 against the printed 5.257; the printed column sums to 32.670 where the definition requires 32.667), the 390 topological charge indices of 39 alkanes equal Galvez et al. 1994 Table 1 to the printed four decimals, and the molecular identification number of Randic 1984 Table IV is reproduced to its eight printed decimals. The gradient-boosted trees, cross-validation, grid search, permutation importance and Tree SHAP are checked against hand solutions and brute-force recomputation, not against printed values, and no published model score is reproduced. Ring and bond counts follow the definitions of a descriptor program rather than a paper, and charge indices of molecules with heteroatoms or multiple bonds are checked on hand-worked values only. Trained only on your data; some extended topochemical and hydrogen E-state descriptors are not built. | Cheminformatics | Partial | 1.10.0 | Hall, Kier 1995; Galvez et al. 1994; Randic 1984; Chen, Guestrin 2016; Breiman 2001; Lundberg et al. 2020 |
Data from engine 1.10.12 (installed on client servers: 1.10.12), generated 2026-11-13. Full citations are on the References page.
Not Offered, on Purpose
Refused until a source we hold supports it, or outside what the product is for.
- Standalone VV10, LC-VV10, B97M-V
- PM6, PM7 and GFN-FF
- PAW in plane-wave DFT (no dataset held under free business terms)
- Writing InChI and InChIKey
- A full molecular G4 run, W1, CBS-QB3
- Surface hopping into S0 and decoherence
- Frequency-dependent or Kohn-Sham ROA
- CASPT2 IPEA and imaginary shifts
- CHARMM36, ff19SB, DES-Amber
- Hosted compute (runs only on your servers)
- ECP gradients
- XAS L edges
- NBO three-centre bonds
- A public API or command line for users
- D3 three-body (ATM) terms: s9 and s42 are not printed
- SCF stability for meta-GGAs, wB97X-V and wB97M-V
- D3 or D4 with double hybrids
- Atomic size adjustment on the Coarse and Normal grids
Run Your Next Molecule Through AiMolSim
See your own molecule optimised, its spectrum computed and the printed reference values shown beside the result.