Brillouin-Wigner perturbation theory and
โ
C. Laughlin; M. R. Woodward; A. T. Amos
๐
Article
๐
1974
๐
John Wiley and Sons
๐
English
โ 340 KB
## Abstract A BrillouinโWigner perturbation expansion is derived for the generalized eigenvalue equation (__F__~0~ + __F__~1~)ฮจ = ฮผ__A__ฮจ. The theory is applied through second order to calculate the groundโstate energies of the helium atom and the hydrogen molecular ion. The results are compared wi