Thermal Properties of Deng-Fan-Eckart Potential model using Poisson Summation Approach

TL;DR

This paper derives thermodynamic properties of diatomic molecules using the Deng-Fan-Eckart potential and Poisson summation, providing accurate energy spectra and wave functions with improved approximation methods.

Contribution

It introduces an improved Pekeris-type approximation and applies the Poisson summation approach to obtain thermodynamic properties and energy spectra for diatomic molecules.

Findings

Results agree well with other methods

Accurate energy spectra for H2, CO, and ScN

Derived unnormalized wave functions

Abstract

The Deng-Fan-Eckart (DFE) potential is as good as the Morse potential in studying atomic interaction in diatomic molecules. By using the improved Pekeris-type approximation, to deal with the centrifugal term, we obtain the bound-state solutions of the radial Schr\"odinger equation with this adopted molecular model via the Factorization Method. With the energy equation obtained, the thermodynamic properties of some selected diatomic molecules(H2 , CO , and ScN ) were obtained using Poisson summation method.. The unnormalized wave function is also derived. The energy spectrum for a set of diatomic molecules for different values of the vibrational n and rotational l are obtained. To show the accuracy of our results, we discuss some special cases by adjusting some potential parameters and also compute the numerical eigenvalue of the Deng-Fan potential for comparison sake. However, it was found out that our results agree excellently with the results obtained via other methods.