2. Speed Of Diatomic Molecules In Shifted Tietz-Wei Potential

by Mark Z.K1., Najoji S.D2 and Eyube E.S3.
1Department of Sciences, Post Primary Schools Management Board, P.M.B. 2260, Yola, Adamawa State, Nigeria
2Department of Basic Sciences, School of General and Remedial Studies. The Federal Polytechnic, P.M.B. 1006, Damaturu, Yobe State, Nigeria
3Department of Physics, Faculty of Physical Sciences, Modibbo Adama University, P.M.B. 2076, Yola, Adamawa State, Nigeria

Abstract
In this work, the shape invariant formalism of SUSYQM is employed in the derivation of approximate equation of bound state energy eigenvalues of the shifted Tietz-Wei potential (STWP). A Pekeris-type approximation model is used to eliminate the centrifugal term of the Schrödinger equation. The expression of bound state energy eigenvalues is used to obtain equation of speed of the system based on the Hellmann-Feynman theorem. Numerical data of bound state energy eigenvalues and speed of two diatomic molecules including O2 (X 3Σg-) and NO (X2 Πf) are obtained. The calculated energies are in excellent agreement with available literature data of the diatomic molecules. The results also show that the speed of the examined diatomic molecules increases with an increase in vibrational quantum number and decreases with increasing rotational quantum number.

Keywords: Shifted Tietz-Wei potential, Tietz-Hua potential, SUSYQM, eigen energies, speed of diatomic molecules