MIXED-EXPONENTIALLY GENERATED WAVE-FUNCTION METHOD FOR GROUND, EXCITED, IONIZED, AND ELECTRON ATTACHED STATES OF A MOLECULE

Wave functions of excited, ionized, and electron attached states are produced by applying the excitator method to the mixed-exponentially generated (MEG) wave function for a ground state. This method is called excited-(EX-)MEG method and the computational algorithm is summarized. The MEG/EX-MEG method is a generalization of the SAC(symmetry adapted cluster)/SAC-CI method. Test applications are given for singlet, triplet, ionized, and anion states of hydrogen fluoride at different internuclear distances (R = Re, 2.1815 Re, and 3.2722 Re). Full-CI calculations are also done for all of these states in order to examine the accuracy of the MEG/EX-MEG method. It is good and reasonably constant among the various states with different energies, different multiplicities, different numbers of electrons, and different internuclear distances, though the sizes of the calculations are smaller than those of the conventional CI.