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The unitary coupled-cluster approach and molecular properties. Applications of the UCC(4) method

✍ Scribed by John D. Watts; Gary W. Trucks; Rodney J. Bartlett

Publisher
Elsevier Science
Year
1989
Tongue
English
Weight
634 KB
Volume
157
Category
Article
ISSN
0009-2614

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✦ Synopsis

The evaluation of the energy and analytical energy gradient of the new unitary coupled-cluster method, UCC(4), are described, and initial numerical results for this method are reported. UCC(4) energies. molecular geometries, vibrational frequencies, and &pole moments are compared with results given by other high-level techmques such as MBPT( 4), CCSDT-I, CCSDT, CISDTQ and FCI.

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