Analytical energy gradient of high-spin multiplet state calculated by the SAC-CI method
نویسندگان
چکیده
A method of calculating analytical energy gradient of high-spin multiplet state by the SAC-CI (symmetry-adaptedcluster configuration-interaction) method is developed and implemented. This method is expected to be a powerful tool in studying the dynamics and properties of molecules having high spin-multiplicities. Good performance of this method is shown for the quartet states of BHþ and C2 and for the quintet states of C2. The SAC-CI general-R method is also extended to the high-spin states, and proved to be useful especially for calculating accurate adiabatic excitation energies of the systems having quasi-degenerate orbital structure. 2001 Published by Elsevier Science B.V.
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