Numerical solution of four-parameter potentials

Abstract

The merits of four-parameter potentials U I, U II and U III proposed by Sarvpreet and Mahajan and their unambigious comparison with the experimental results have been demonstrated by solving the Schrödinger wave equation numerically. The fourth-order Runge–Kutta method is used to obtain the theoretical vibronic eigenvalues for the normal electronic states of Li 2, Cl 2, CO, I 2, ICl, HF, Rb 2, Cs 2 and an excited state of XeO molecule. The results show that U I and U II yield eigenvalues which are more close to U RKR compared to U W potential function of Wei Hua for all but COX 1Σ g + state where U W is only slightly better. The performance of U I is excellent particularly for the alkali molecules. The efficacy of U I is illustrated by taking the electronic state X 3Σ g − of S 2 whose experimental data of vibronic states, unlike the above-mentioned states, is not extensive. The value of D e is obtained to be 35 500±250 cm −1 which is close to 35 999 cm −1 obtained from the predissociation limit.