✦ LIBER ✦

An evaluation of three direct MC-SCF procedures

✍ Scribed by Michael Frisch; Ioannis N. Ragazos; Michael A. Robb; H. Bernhard Schlegel

Book ID: 103035368
Publisher: Elsevier Science
Year: 1992
Tongue: English
Weight: 431 KB
Volume: 189
Category: Article
ISSN: 0009-2614
DOI: 10.1016/0009-2614(92)85244-5

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✦ Synopsis

The direct MC-SCF approach for modest active spaces is evaluated for (a) extended basis sets on small molecules and (b) modest sets on extended systems. An algorithm that scales as n,'N' ( na= number of active orbitals, N= number of AO) using Fock matrices appears to be quite efficient until n, gets to 8 where an algorithm that scales as n.N4 using 3/4 transformed integrals begins to become competitive. The storage requirement for the J and K operators in the n,N" algorithm has been removed with the cost of an additional direct Fock matrix construction.

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