Optical absorption/emission of strontium dimer molecule under noncentral potential energy

The study of noncentral potential effects and mirror-image symmetry in strontium dimer (Sr $$_2$$ ) spectroscopy remains an active area of research, with important aspects for quantum mechanical models and practical applications. In this study, we derived potential energy curves (PECs) for ground and excited states by fitting q-deformed Morse PECs to RKR and ab initio data, quantifying their accuracy in reproducing observed optical absorption transitions. We also obtained absorption and emission peaks from q-deformed Morse-fitted PECs through mirror-image symmetry. By modeling ring-shaped deformations on absorbance spectra, we showed reduced intensity distributions related to the forbidden transitions. The results demonstrate that while the q-deformed Morse PEC effectively predicts most vibrational progressions in the optical spectra of Sr $$_2$$ , deviations arise from noncentral interactions in both ground and excited electronic states. These outcomes advance the spectroscopic modeling of strontium dimer and analogous systems with complex or combined potential energy ways.