A note on vibrational perturbation theory for tunneling splitting in a symmetric double well potential.

J Chem Phys

Chemical and Biological Physics Department, Weizmann Institute of Science, 76100 Rehovoth, Israel.

Published: July 2024

The modified version of second and fourth order vibrational perturbation theory, whereby the Euclidean action for tunneling is computed on the inverted potential at a shifted energy that is ℏ2 dependent, is applied to a symmetric double well quartic potential. The mean energies of the doublets in each well are also computed using vibrational perturbation theory. Results show that the modified vibrational perturbation theory significantly improves the estimates of tunneling splitting energies both for the ground state and for excited state doublets.

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http://dx.doi.org/10.1063/5.0220517DOI Listing

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