QUASI-DEGENERACY AND COUPLED-PAIR THEORIES

被引:41
作者
ADAMS, BG
JANKOWSKI, K
PALDUS, J
机构
[1] Quantum Theory Group, Department of Applied Mathematics, University of Waterloo, Waterloo
关键词
D O I
10.1016/0009-2614(79)87124-9
中图分类号
O64 [物理化学(理论化学)、化学物理学];
学科分类号
070304 ; 081704 ;
摘要
The source of differences between the exact and approximate coupled-pair methods is investigated for the Be ground state. We find that the discrepancy between the coupled-pair theory and its linear version is due to quasi-degeneracy effects. A very accurate CEPA-type approximation is also discussed. © 1979.
引用
收藏
页码:144 / 148
页数:5
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