The twofold diabatization of the KRb $(1\sim 2{)}^1\Pi$ complex in the framework of \emph{ab initio} and deperturbation approaches

Abstract

We performed a diabatization of the mutually perturbed $1^1\Pi$ and $2^1\Pi$ states of KRb based on both electronic structure calculation and direct coupled-channel deperturbation analysis of experimental energies. The potential energy curves (PECs) of the diabatic states and their scalar coupling were constructed from the \textit{ab initio} adiabatic PECs by analytically integrating the radial $⟨{\psi }_1^{ad}|\partial /\partial R|{\psi }_2^{ad}⟩$ matrix element obtained by a finite-difference method. The diabatic potentials and electronic coupling function were refined by the least squares fitting of the rovibronic termvalues of the $1^1\Pi \sim 2^1\Pi$ complex. The empirical PECs combined with the coupling function as well as the diabatized spin-orbit coupling and transition dipole matrix elements are useful for further deperturbation treatment of both singlet and triplet states manifold.

References in corpus (1)

• The coupling of the X${}^1{\Sigma }^{+}$ and a${}^3{\Sigma }^{+}$ states of KRb