Abstract
We solved the Klein–Gordon equation using the Nikiforov–Uvarov (NU) method with Eckart–Hellmann potential (EHP) model with approximation to the centrifugal term. The analytical expression of the ro-vibrational energy spectra in relativistic, non-relativistic and the corresponding normalised wavefunction were obtained. The numerical bound states energy for various screening parameters at different quantum states and ro-vibrational energies of EHP for VH, TiH, NiC, TiC and CuLi diatomicmolecules were computed. We have also obtained the expectation values of ,
and
using Hellmann–Feynman theorem for the selected diatomic molecules. Graphically, we have illustrated the variation of ro-vibrational energies and expectation values of
,
and
. Four special cases of EHP where obtained and the results were in excellent agreements with the existing literature.
GRAPHICAL ABSTRACT
![](/cms/asset/240a23d0-9d8e-4b1f-a29a-ee8444292685/tmph_a_1956615_uf0001_oc.jpg)
Disclosure statement
No potential conflict of interest was reported by the author(s).