A density functional for core-valence correlation energy

作者：Ranasinghe Duminda S^*; Frisch Michael J; Petersson George A

来源：Journal of Chemical Physics, 2015, 143(21): 214111.

DOI：10.1063/1.4935973

A density functional, epsilon(CV-DFT)(rho(c),rho(v)), describing the core-valence correlation energy has been constructed as a linear combination of epsilon(corr)(LYP) (rho(c)), epsilon(corr)(VWN5) (rho(c),rho(v)), epsilon(corr)(PBE) (rho(c),rho(v)), epsilon(ex)(Slater)(rho(c),rho(v)), epsilon(ex)(HCTH) (rho(c),rho(v)), epsilon(ex)(HF)(rho(c),rho(v)), and FCV-DFT (N-i, Z(i)), a function of the nuclear charges. This functional, with 6 adjustable parameters, reproduces (+/- 0.27 kcal/mol rms error) a benchmark set of 194 chemical energy changes including 9 electron affinities, 18 ionization potentials, and 167 total atomization energies covering the first-and second-rows of the periodic table. This is almost twice the rms error (+/- 0.16 kcal/mol) obtained with CCSD(T)/MTsmall calculations, but less than half the rms error (+/- 0.65 kcal/mol) obtained with MP2/GTlargeXP calculations, and somewhat smaller than the rms error (+/- 0.39 kcal/mol) obtained with CCSD/MTsmall calculations. The largest positive and negative errors from epsilon(CV-DFT)(rho(c),rho(v)) were 0.88 and -0.75 kcal/mol with the set of 194 core-valence energy changes ranging from +3.76 kcal/mol for the total atomization energy of propyne to -9.05 kcal/mol for the double ionization of Mg. Evaluation of the epsilon(C

• 出版日期2015-12-7