torchani.constants

Atomic constants, and Density Functional constants

If you use these constants in your work please cite the corresponding article(s).

Values for electronegativity and hardness for elements H-Bk, all for neutral atoms, and are taken from Table 3 of

Carlos Cardenas et. al. Benchmark Values of Chemical Potential and Chemical Hardness for Atoms and Atomic Ions (Including Unstable Ions) from the Energies of Isoelectronic Series.

DOI: 10.1039/C6CP04533B

Atomic masses supported are the first 119 elements (consistent with ASE) are taken from:

Atomic weights of the elements 2013 (IUPAC Technical Report). Meija, J., Coplen, T., Berglund, M., et al. (2016). Pure and Applied Chemistry, 88(3), pp. 265-291. Retrieved 30 Nov. 2016, from doi:10.1515/pac-2015-0305

DFT-D3(BJ) constants for different density functionals taken from the psi4 source code, citations: A. Najib, L. Goerigk, J. Comput. Theory Chem., 14 5725, 2018) N. Mardirossian, M. Head-Gordon, Phys. Chem. Chem. Phys, 16, 9904, 2014

Except for B97-3c taken from https://aip.scitation.org/doi/pdf/10.1063/1.5012601

And for wB97X taken from TODO: where?

Covalent radii are in angstroms, and are are used for the calculation of coordination numbers in DR. Taken directly from Grimme et. al. dftd3 source code, in turn taken from Pyykko and Atsumi, Chem. Eur. J. 15, 2009, 188-197 Values for metals decreased by 10 % with respect to Pyykko et. al.

Empirical Q in atomic units, correspond to sqrt(0.5 * sqrt(Z) * <r**2>/<r**4>). In Grimme’s code these are “r2r4”, and are used to calculate the C8 values. These are precalculated values. For details on their calculation consult the DFT-D3 papers

XTB repulsion data extracted from Grimme et. al. paper https://pubs.acs.org/doi/10.1021/acs.jctc.8b01176