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On the use of partitioning theory in configuration interaction

✍ Scribed by G. Raşeev

Publisher
Elsevier Science
Year
1977
Tongue
English
Weight
654 KB
Volume
47
Category
Article
ISSN
0009-2614

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✦ Synopsis

We introduce a procedure for the CI description of energy surfaces based on an extension of the concept of a partiaUy tilled Cl matrix (called nearly empty matrix (NEM)) and the unique selected configuration list (USCL). An NEM-USCL compared to a full matrh calculatzon (ratio of calculated CI matrix elements l/7) gives a difference in the optimized geometry parameters of methylene of A(C-H) = 0.0044 A and A(HCH) = 0.6". * After the completion of this work, we learned about a method close to ours developed by R-C. Raffenetti. K. Hsu and I. Shavitt, Theoret. Chim. Acta (to be published). Their procedure takes away from a given list a variable number of configurations but the overall contribution to the energy of these discarded configurations is constant.

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