Modified group-projector technique: Subgroups and generators

Abstract

Instead of the usual procedure involving the family of group operators, only the projector of the identity representation is used to obtain the symmetry-adapted basis. For the product groups, this projector is factorized to the subgroups. So, the whole procedure is reduced to the eigenvalue problem for the operators representing the generators. Avoiding summation over the group, the method is suitable for computer implementations even for infinite groups. Some applications are discussed.