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Invariance properties of the moments of the hamiltonian matrix as a test of the correctness of configuration interaction programs

โœ Scribed by Geerd H.F. Diercksen; Jacek Karwowski


Publisher
Elsevier Science
Year
1987
Tongue
English
Weight
530 KB
Volume
47
Category
Article
ISSN
0010-4655

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โœฆ Synopsis


An invariance of the spectrum of a full configuration interaction (CI) matrix with respect to unitary transformations of the orbital basis set is frequently used as a test of the correctness of CI programs. In this paper we argue that using instead the invariance properties of the first two moments of the spectrum of the matrix is both simpler and more conclusive. Explicit formulae for the moments are derived and their usefulness is illustrated by several examples.


๐Ÿ“œ SIMILAR VOLUMES


A numerical test on the size consistency
โœ J. Rubio; A. Povill; F. Illas; J.P. Malrieu ๐Ÿ“‚ Article ๐Ÿ“… 1992 ๐Ÿ› Elsevier Science ๐ŸŒ English โš– 656 KB

The size consistency of selected multireference CI approaches is tested on two model problems, namely seven non-interacting H, molecules at their equilibrium bond length r, or at 2r, and seven non-interacting Ne atoms, In all cases the results obtained from the two-class CIPSI method (which is a mul