Lower Bounds for the Energy Levels of Anharmonic Oscillators
- 15 November 1965
- journal article
- research article
- Published by AIP Publishing in The Journal of Chemical Physics
- Vol. 43 (10) , S186-S189
- https://doi.org/10.1063/1.1701484
Abstract
The lower‐bounds method presented by Löwdin in the preceding paper has been applied to oscillators perturbed by third‐ and fourth‐power terms in the potential‐energy expression. For favorable cases agreement between upper and lower bounds is easily carried to many more figures than are likely to be physically significant. In many cases the lower bounds agreed more closely to the true eigenvalue than did the corresponding upper bounds. For a given basis set, this method gives closer bounds than that of Bazley and Fox, except for energy levels too high to be satisfactorily treated in the given basis. The only disadvantage found was that for close bounds double precision proved necessary, indicating more than ordinary loss of computational accuracy.Keywords
This publication has 3 references indexed in Scilit:
- Studies in Perturbation Theory. XI. Lower Bounds to Energy Eigenvalues, Ground State, and Excited StatesThe Journal of Chemical Physics, 1965
- Studies in perturbation theoryJournal of Molecular Spectroscopy, 1963
- Lower Bounds for Eigenvalues of Schrödinger's EquationPhysical Review B, 1961