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arXiv · 1710.07730

Comment on "The Rotation-Vibration Spectrum of Diatomic Molecules with the Tietz-Hua Rotating Oscillator"

A. Khodja·F. Benamira·L. Guechi
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Abstract

We present arguments demonstrating that the application of the Nikiforov-Uvarov polynomial method to solve the Schrödinger equation with the Tietz-Hua potential is valid only when $e^{-b_{h}r_{e}}\leq c_{h}<1$ and $r_{0}<r<+\infty $. In particular, it is pointed out that the numerical results with $c_{h}\neq 0$ for the diatomic molecules $\mathrm{HF}$, $\mathrm{N}_{2}$, $\mathrm{I}_{2}$, $\mathrm{H}_{2}$, $\mathrm{O}_{2}$ and $\mathrm{O}_{2}^{+}$ given in Tables 3-5 by Hamzavi and co-workers are wrong. When $-1\leq c_{h}<0$ or $0<c_{h}<e^{-b_{h}r_{e}}$, this approach is not suitable. In both cases, it is shown that the solutions of the Schrödinger equation are expressed in terms of the generalized hypergeometric functions $_{2}F_{1}\left( a,b,c;z\right) $. The determination of the energy levels requires the solution of transcendantal equations involving the hypergeometric function by means of the numerical procedure.

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A. Khodja, F. Benamira, L. Guechi. 2017-10-20. Comment on "The Rotation-Vibration Spectrum of Diatomic Molecules with the Tietz-Hua Rotating Oscillator". https://doi.org/10.1002/qua.25334

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