S. Cohen, T.O. Sedgwick, et al.
MRS Proceedings 1983
A linear M-O-M (M=metal, O=oxygen) cluster embedded in a Madelung field, and also including the quantum effects of the neighboring ions, is used to represent the alkaline-earth oxides. For this model an ab initio wave function is constructed as a linear combination of Slater determinants written in an atomic orbital basis set, i.e., a valence-bond wave function. Each valence-bond determinant (or group of determinants) corresponds to a resonating valence-bond structure. We have obtained ab initio valence-bond cluster-model wave functions for the electronic ground state and the excited states involved in the optical-gap transitions. Numerical results are reasonably close to the experimental values. Moreover, the model contains the ionic model as a limiting case and can be readily extended and improved. © 1993 The American Physical Society.
S. Cohen, T.O. Sedgwick, et al.
MRS Proceedings 1983
J.V. Harzer, B. Hillebrands, et al.
Journal of Magnetism and Magnetic Materials
I.K. Pour, D.J. Krajnovich, et al.
SPIE Optical Materials for High Average Power Lasers 1992
J.R. Thompson, Yang Ren Sun, et al.
Physica A: Statistical Mechanics and its Applications