Analysis of strongly coupled electronic states in diatomic molecules: Low-lying excited states of RbCs

Abstract

Analysis and assignment of spectra involving the lowest excited states of the heavier alkali-metal atom dimers are complicated by the strong spin-orbit coupling elements. Here we report an analysis of the Fourier-transform spectroscopy data from laser-induced fluorescence of the coupled $A{}^{1}{\ensuremath{\Sigma}}^{+}$ and $b{}^{3}\ensuremath{\Pi}$ states of RbCs, using the discrete variable representation. Fitted parameters are given and special effects due to strong coupling are discussed.