Ab initio study of NaRb+: Potential energy curves, spectroscopic constants and atomic polarizabilities

Using an ab initio approach involving a non-empirical pseudopotentials for Na and Rb atoms, the adiabatic potential energy curves of 26 electronic states of NaRb+ ionic molecule dissociating up to Na(4p) + Rb+ and Na+ + Rb(7s) have been investigated. Their molecular spectroscopic constants have been derived and compared with the available theoretical works. Furthermore, the transition dipole moments from X2Σ+ and 22Σ+ to higher excited states have been determined. Numerous avoided crossings between electronic states of 2Σ+ and 2Π symmetries have been localised and analysed. Their existences are related to the charge transfer process between the two ionic systems Na+Rb and NaRb+. The accurate potential energy curves have been exploited to realize a long-range vibrational level spacing analysis using the WKB semi-classical approximation in order to extract the Na and Rb atomic static dipole polarizabilities. A very good agreement between our static dipole polarizabilities and the available experimental and theoretical works has been observed.