A set of commuting operators and R(3) scalars for the complete classification of quadrupole phonon-states

Abstract
A method is developed for constructing operator forms which commute with the Casimir operators of the groups appearing in the chain U(5) ⊆SU(5) ⊆R(5) ⊆R(3) ⊆ (2), according to which the quadrupole‐phonon states are usually classified. An expression for such operator is given.