DYNAMICS OF DEGENERATE LOCAL EXCITATIONS IN CUBIC METALS

The problem of an isolated ion with a total angular momentum J in a cu bic metal is analyzed by the technique of Abrikosov pseudofermions. A system of generalized kinetic equations is constructed. The particular example J = 5/2 is studied in the case in which the ground state is t he quartet GAMMA8 (CeB6). The central peak in the susceptibility can b e described by a sum of two Lorentzians, one of which is narrower and higher than the other. This multimode behavior is shown to be a genera l phenomenon when a degenerate multiplet is not a doublet and does not constitute all the states of the system.