Relativistic selfhyphen;consistenthyphen;field (RSCF) theory for closedhyphen;shell molecules

摘要

The relativistic Hartreendash;Fockndash;Roothaan (RHFR) formalism for closedhyphen;shell molecules is given. The wavefunction for such systems is taken as a single Slater determinant of 4hyphen;component molecular spinors (MS), where each MS is written as a linear combination of atomic spinors (LCAS/MS). The radial part of the atomic spinor (AS) is expanded in terms of Slaterhyphen;type basis functions (STBF). The relativistic electronic Hamiltonian for the molecular system (in Bornndash;Oppenheimer approximation) is the sum of Dirac Hamiltonians plus the interelectronic Coulomb repulsion and the magnetic part of the Breit interaction, but the retardation term is neglected at present. The reduction of the matrix elements of the relativistic Hamiltonian in terms of the nonrelativistichyphen;type matrix elements is shown for any molecular system. Expressions for the matrix elements of the abovehyphen;mentioned relativistic Hamiltonian are given for diatomics.