| Abstract: | In order to avoid the determination of the perturbed wave function in the susceptibility calculation of closed shell molecules, several authors have developed gauge-variation methods based on Rebane's work. The present work illustrates that introduction of a certain restriction in the gauge-variation method makes the susceptibility calculations exceptionally simple. The restriction involves the use of the Coulomb gauge so that the gauge-function satisfies Laplace's equation. The restriction was dictated by the demonstration of gauge-invariance of the Rayleigh–Schrouml;dinger perturbation theory of diamagnetism. The method with the prescribed restriction has been applied to the H2O molecule, as an example, to demonstrate the advantages. |
