Exact and Poisson summation thermodynamic properties for diatomic molecules with shifted Tietz potential

Abstract

We obtained in detail the energy spectra of the shifted Tietz potential using factorization method within the framework of non-relativistic quantum mechanics. With this energy, the thermodynamic properties of the electronic state of $$ 3^{3}\Sigma _{g}^{ + } $$ of $$ {\text{Cs}}_{2} $$ diatomic molecules are obtained using exact and Poisson summation formalism for the shifted Tietz potential, with adjustable parameter (optimization) appearing in the shifted Tietz potential function ranging from $$ C_{h} \, = \, \pm \,\frac{1}{5},\; \pm \,\frac{1}{8} $$ and $$ \pm \,\frac{1}{4} $$ respectively. Free energy F, internal energy U, entropy S and specific heat C are also calculated. In each case, the exact and Poisson summation states are plotted for the electronic state $$ 3^{3}\Sigma _{g}^{ + } $$ of $$ {\text{Cs}}_{2} $$ diatomic molecules with various optimization parameters.