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Open-shell coupled-cluster method: Direct calculation of excitation energies

✍ Scribed by Uzi Kaldor; Azizul Haque

Publisher
Elsevier Science
Year
1986
Tongue
English
Weight
381 KB
Volume
128
Category
Article
ISSN
0009-2614

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✦ Synopsis

An open-shell coupled-cluster method for the direct calculation of excitation energies is presented.

As a first test, applications to atomic Be and Ne are carried out, with exact inclusion of T, and T2 operators and lowest-order inclusion of T3. Quasicomplete model spaces are used. Two ionization potentials and 16 excitation energies are calculated. They all agree with experiment to 0.15 eV.

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