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Direct algorithm for the random-phase approximation

โœ Scribed by V. G. Zakrzewski; O. Dolgounitcheva; J. V. Ortiz

Publisher
John Wiley and Sons
Year
1996
Tongue
English
Weight
525 KB
Volume
60
Category
Article
ISSN
0020-7608

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โœฆ Synopsis

An algorithm for calculating excitation energies and transition moments in the randomphase approximation (RPA) of the polarization propagator is presented. The algorithm includes direct solution of the RPA eigenvalue problem and direct evaluation of products of superoperator Hamiltonian matrices with excitation vectors. Given sufficient memory, only one integral evaluation step per iteration is needed. Illustrative calculations on the excitation energies and oscillator strengths of ethylene are presented.

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