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arXiv · 1312.7051

Symmetry-adapted formulation of the combined G-particle-hole Hypervirial equation and Hermitian Operator method

Diego R. Alcoba·Gustavo E. Massaccesi·Ofelia B. Oña·Juan J. Torres·Luis Lain·Alicia Torre
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Abstract

High accuracy energies of low-lying excited states, in molecular systems, have been determined by means of a procedure which combines the G-particle-hole Hypervirial (GHV) equation method [Alcoba et al. Int. J. Quantum Chem. 109:3178 (2009)] and the Hermitian Operator (HO) one [Bouten et al. Nucl. Phys. A 202:127 (1973)]. This paper reports a suitable strategy to introduce the point group symmetry within the framework of the combined GHV-HO method, what leads to an improvement of the computational efficiency. The resulting symmetry-adapted formulation has been applied to illustrate the computer timings and the hardware requirements in selected chemical systems of several geometries.

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Diego R. Alcoba, Gustavo E. Massaccesi, Ofelia B. Oña, Juan J. Torres, Luis Lain, Alicia Torre. 2013-12-26. Symmetry-adapted formulation of the combined G-particle-hole Hypervirial equation and Hermitian Operator method. https://arxiv.org/abs/1312.7051

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