A QUANTUM-CHEMICAL DETERMINATION OF DIABATIC STATES

A simple electronic-structure-based construction of diabatic states fr om adiabatic states is formulated. It is accomplished by maximizing th e configurational uniformity of the diabatic states with respect to th e dominant configurations throughout the entire coordinate space. No c onfigurational constraints are introduced. No matrix elements of addit ional, derivative, or nonderivative operators have to be calculated. T he matrix elements between the diabatic states are simply expressible in terms of the adiabatic energies and wave function coefficients.