Low-energy unphysical saddle in polynomial molecular potentials
Chemical Physics
2014-02-04 v3 Condensed Matter
Abstract
Vibrational spectra of polyatomic molecules are often obtained from a polynomial expansion of the adiabatic potential around a minimum. For several molecules, we show that such an approximation displays an unphysical saddle point of comparatively small energy, leading to a region where the potential is negative and unbounded. This poses an upper limit for a reliable evaluation of vibrational levels. We argue that the presence of such saddle points is general.
Cite
@article{arxiv.physics/0311016,
title = {Low-energy unphysical saddle in polynomial molecular potentials},
author = {Alessio Del Monte and Nicola Manini and Luca G. Molinari and Gian Paolo Brivio},
journal= {arXiv preprint arXiv:physics/0311016},
year = {2014}
}
Comments
The preprint version of the published Mol. Phys. paper, 19 pages, 3 figures