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The N2 problem in molecular CI calculations

✍ Scribed by A. Meunier; B. Levy; G. Berthier

Book ID
104578904
Publisher
John Wiley and Sons
Year
1976
Tongue
English
Weight
492 KB
Volume
10
Category
Article
ISSN
0020-7608

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✦ Synopsis

Abstract

The possible existence of spurious terms increasing as the square of the number of electrons is theoretically proved for the CI treatments of molecules limited to single and double excitations, and is revealed by some numerical calculations (alcanes and juxtaposed hydrogen molecules). An improved perturbation scheme is suggested in order to evaluate the CI energy lowering more carefully. Covergence difficulties are found for larger systems (benzene).

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