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A direct CI method with a multiconfigurational reference state

✍ Scribed by Björn O. Roos; Per E. M. Siegbahn

Book ID
104579801
Publisher
John Wiley and Sons
Year
1980
Tongue
English
Weight
913 KB
Volume
17
Category
Article
ISSN
0020-7608

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✦ Synopsis

Abstract

A method for direct configuration–interaction (CI) calculations with a multiconfigurational reference function is described. The reference state can contain several closed‐shell electronic configurations and the CI expansion comprises all single and double replacements out of all these configurations. The resulting secular problem is solved using a variation‐perturbation method. A number of examples are given showing the efficiency of the method. The largest CI expansion used in calculations with this program so far contains 76,471 spin‐ and space‐symmetrized configurations.

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