An atomic kinetic energy functional with full Weizsacker correction
AUTOR(ES)
Acharya, Prabhat K.
RESUMO
A functional is proposed for representing the electronic kinetic energy of the ground state of an N-electron atom or ion in terms of its electron density, [Formula: see text] Here Tw is the Weizsacker quantity (⅛)∫(∇ρ·∇ρ/ρ)dτ and T0 is the Thomas-Fermi quantity CF ∫ ρ5 / 3dτ. From Hartree-Fock data on 55 neutral atoms, C = 1.412 ± 0.033; for 1200 atoms and ions, C = 1.332 ± 0.053. The proposed functional gives the derivative δT/δρ its most important correct properties. The term Tw is shown to give the kinetic energy of the K shell, whereas the term (C/N⅓)T0 gives an incorrect statistical estimate of that energy. An alternative correction -(C/N⅓)T gives even better results.
