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10004.a.ChemRxiv....2vsN.elektron.HF-SCF.ab=1+zeta.a=0.Vee-QUASI-LINEAR.pdf (589.04 kB)

Quasi-linear dependence of Coulomb forces on coupling strength parameter in the non-relativistic electronic Schrödinger equation and its consequences in Hund’s rule, Mølle -Plesset perturbation- , virial - , Hohenberg-Kohn - and Koopmans theorem

submitted on 02.09.2017 and posted on 07.09.2017 by Sandor Kristyan

The extended non-relativistic electronic Hamiltonian, HÑ+ Hne+ aHee, is linear in coupling strength parameter (a), but its eigenvalues (interpreted as electronic energies) have only quasi-linear dependence on “a”. No detailed analysis has yet been published on the ratio or participation of electron-electron repulsion energy (Vee) in total electronic energy – apart from virial theorem and the highly detailed and well-known algorithm for Vee, which is calculated during the standard HF-SCF and post-HF-SCF routines. Using a particular modification of the SCF part in the Gaussian package we have analyzed the ground state solutions via the parameter “a”. Technically, this modification was essentially a modification of a single line in an SCF algorithm, wherein the operator rij-1 was overwritten as rij-1 ® arij-1, and used “a” as input. The most important finding beside that the repulsion energy Vee(a) is a quasi-linear function of “a”, is that the extended 1st Hohenberg-Kohn theorem (Y0(a=1) Û Hne Û Y0(a=0)) and its consequences in relation to “a”. The latter allows an algebraic transfer from the simpler solution of case a=0 (where the single Slater determinant is the accurate form) to the realistic wanted case a=1. Moreover, we have generalized the emblematic theorems in the title in relation to the coupling strength parameter.


OTKA-K 2015-115733 and 2016-119358



  • Computational chemistry and modeling
  • Theory

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Research Centre for Natural Sciences, Hungarian Academy of Sciences



ORCID For Submitting Author


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