Uncoupled Hartree-Fock perturbation theory and the Pople-Schofield approximation
- 15 December 1974
- journal article
- research article
- Published by AIP Publishing in The Journal of Chemical Physics
- Vol. 61 (12), 5066-5071
- https://doi.org/10.1063/1.1681850
Abstract
The first‐order perturbation equation in UCPT is derived in a form which reflects the essential lack of uniqueness of the perturbed orbital. The functionals leading to this equation and the other forms of the first‐order equation are compared and this functional found to be best, although equivalent to the others if additional conditions are applied to their variation. The Pople‐Schofield approximation, which is frequently applied to simplify the computation of the variational functional, is examined and found to be exact in the sense that H0 can be constructed to make it so. A simpler way of regarding the Pople‐Schofield approximation is presented using a method due to Hirschfelder and originally designed to deal with exchange forces.Keywords
This publication has 14 references indexed in Scilit:
- Second-order properties of bondsChemical Physics Letters, 1973
- The OPIT system I. A file-handling scheme for data in large applications programsComputer Physics Communications, 1973
- Variational approximations to time-dependent Hartree-Fock theoryMolecular Physics, 1973
- Perturbation theory for exchange forces, IChemical Physics Letters, 1967
- Hartree—Fock Theory of Atomic PropertiesThe Journal of Chemical Physics, 1967
- Molecular SCF Calculations on CH4, C2H2, C2H4, C2H6, BH3, B2H6, NH3, and HCNJournal of the American Chemical Society, 1966
- Electric Polarizability of Some Diatomic MoleculesThe Journal of Chemical Physics, 1963
- Atomic polarizabilities and shielding factorsAdvances in Physics, 1962
- Studies in Molecular Structure. II. LCAO-MO-SCF Wave Functions for Selected First-Row Diatomic MoleculesReviews of Modern Physics, 1960
- Electric polarizability of atoms and moleculesPhilosophical Magazine, 1957