Charge localization in diatomic ions investigated with a new dipole moment driven approach. Test for Ne2+ and (ArNe)+

A novel method is proposed to develop charge-localized representations of the electronic structure of singly ionized dimers of rare gases. The method is based on an orthogonal transformation of the adiabatic dimer dipole moment matrix to a new basis in which the matrix is as close as possible to its point charge approximation. Upon general considerations and derivations, the method is applied to two specific cases, a homonuclear dimer of Ne2+ and a heteronuclear dimer of (NeAr)+. High-level ab initio calculations have also been performed for both systems to get accurate input data and are reported.