Dispersion-Corrected Atom-Centered Potentials for Phosphorous

Dispersion-corrected atom-centered; potentials (DCACPs) for the element phosphorus were generated and tested for the BLYP, BP, and PBE generalized gradient approximations of the exchange-correlation functional. The accuracy and transferability of the DCACPs were tested by evaluating the interaction energy of different weakly bound molecular systems (P-2, PH3, and PN dimers). These results were compared to reference CCSD(T) calculations and standard density functional theory (DFT). The DCACP were also tested in the case of condensed phase systems. Specifically, the density and cohesive energies of beta-white and black phosphorus were estimated and compared to available experimental data. Our results show an overall strong improvement both at the qualitative and quantitative level, with respect to uncorrected generalized gradient approximation DFT results for all three functionals. In particular, BLYP-corrected results show the maximal transferability, reporting for all systems a deviation from CCSD(T) results of less than 1% in the predicted binding energies.