Transition operator between multipole states and their tensor structure

An operator that determines the reeursion of multipole moments is found. It is shown that the use of multipole moments as functions of the coordinates of a point charge is in some sense preferable to the use of spherical functions to calculate the energy and correlation characteristics of radiation, to study matrix elements of multipole moments, and in the theory of addition of angular momentum. The quantum-mechanical meaning of multipole states and the transition operator defining the creation of an “angularmomentum quantum” is elucidated.