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arXiv · 1409.4120

Perturbation theory by the moment method and point-group symmetry

Francisco M. Fernández
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Abstract

We analyze earlier applications of perturbation theory by the moment method (also called inner product method) to anharmonic oscillators. For concreteness we focus on two-dimensional models with symmetry $C_{4v}$ and $C_{2v}$ and reveal the reason why some of those earlier treatments proved unsuitable for the calculation of the perturbation corrections for some excited states. Point-group symmetry enables one to predict which states require special treatment.

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Francisco M. Fernández. 2014-09-14. Perturbation theory by the moment method and point-group symmetry. https://arxiv.org/abs/1409.4120

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