<i>A</i> <i>b</i> <i>i</i> <i>n</i> <i>i</i> <i>t</i> <i>i</i> <i>o</i> ground state properties of neutral X2Y and ionic X2Y+ (X,Y=Li, Na, K) alkali trimers

Abstract

The electronic ground state properties of neutral and singly charged alkali trimers involving Li, Na, and K atoms (homogeneous and heterogeneous trimers) are studied using ab initio core pseudopotentials and configuration interaction. Equilibrium geometries, dissociation energies, vertical and adiabatic ionization potentials are given. All systems are found to be triangular. Neutral light–light–heavy trimers (Li2Na, Li2K, and Na2K) have Cs equilibrium geometry while neutral light–heavy–heavy trimers (LiNa2, LiK2, and NaK2) have C2v geometry. All ionic species are isosceles. The ionization potentials are in good agreement with available experimental results.