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Gradient theory applied to restricted (open-shell) Møller—Plesset theory

✍ Scribed by David J. Tozer; Jamie S. Andrews; Roger D. Amos; Nicholas C. Handy

Publisher
Elsevier Science
Year
1992
Tongue
English
Weight
592 KB
Volume
199
Category
Article
ISSN
0009-2614

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✦ Synopsis

A theory for the evaluation of the gradient ofthe second-order restricted open-shell Meller-Plesset (RMP) energy is presented. It is not straightfonvard because the use of semi-canonical orbitals forms an essential part of RMP theory. Stationary conditions which determine the semi-canonical orbitals are derived; these are then differentiated to give the associated coupled perturbed equations. Au application to the reaction CH,+C,H,+CPH, is presented, which shows that the energy barrier to reaction is signiticantly decreased compared to the use of unrestricted Muller-Plesset theory.

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