Impact of topological defects and Yukawa potential combined with inverse square on eigenvalue spectra of diatomic molecules O ₂, NO, LiH, HCl

Abstract

In this paper, we investigate a quantum system composed of non-relativistic particles interacting with an external potential while in the presence of a topological defect produced by a point-like global monopole. We derive the radial equation of the Schrödinger equation for this system, considering a Yukawa potential combined with inverse square potential within the backdrop of a point-like global monopole. To determine the eigenvalue solutions for this quantum system, we employ a suitable approximation scheme known as the Pekeris approximation. This approximation is applied to the centrifugal term, and we solve the resulting radial equation using the parametric Nikiforov-Uvarov (NU) method. Subsequently, we examine the quantum system when only Yukawa potential is present, and we obtain the eigenvalue solutions using the same procedure. In both cases, we observe that the presence of the global monopole topological defect has a significant impact on the energy spectrum of quantum particles interacting with an external potential. To illustrate this effect, we consider a few diatomic molecules, such as O2, NO, LiH, and HCl. We present the energy spectrum and compare our results with previously published findings in the literature. Furthermore, we generate several plots to visually depict the influence of the global monopole on the energy eigenvalues for these different molecules.