2003/09/30 by Xiao‐Yin Pan, Xiao-Yin Pan, Viraht Sahni
Chemistry · Physics and Astronomy · #Advanced Chemical Physics Studies #Advanced Physical and Chemical Molecular Interactions #Atomic physics #Coulomb #Density functional theory #Eigenvalues and eigenvectors #Electron #Fermion #Ion #Ionization #Ionization energy #Kinetic energy #Pauli exclusion principle #Physics #Quantum mechanics #Quantum, superfluid, helium dynamics #Schrödinger equation #Wave function #cond-mat.mtrl-sci
paper · pdf · doi:10.1063/1.1647514
27 pages, 1 table, 13 figures
arxiv created 2003/11/14 · openalex publication_date 2004/03/11 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
In this paper we perform a quantal density functional theory (Q-DFT) study of the hydrogen molecule in its ground state. In common with traditional Kohn-Sham density functional theory, Q-DFT transforms the interacting system as described by Schrodinger theory, to one of noninteracting fermions--the S system--such that the equivalent density, total energy, and ionization potential are obtained. The Q-DFT description of the S system is in terms of "classical" fields and their quantal sources that are quantum-mechanical expectations of Hermitian operators taken with respect to the interacting and S system wave functions. The sources, and hence the fields, are separately representative of all the many-body effects the S system must account for, viz. electron correlations due to the Pauli exclusion principle, Coulomb repulsion, and correlation-kinetic effects. The local electron-interaction potential energy of each model fermion is the work done to move it in the force of a conservative effective field that is the sum of the individual fields. The Hartree, Pauli, Coulomb, and correlation-kinetic energy components of the total energy are also expressed in virial form in terms of the corresponding fields. The highest occupied eigenvalue of the S system is the negative of the ionization potential energy. The Q-DFT analysis of the hydrogen molecule is performed employing the highly accurate correlated wave function of Kolos and Roothaan.