2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/147506Impurity ions with orbitally degenerate ground electronic configuration embedded in metals are subjects to both the Kondo effect and the Jahn-Teller instability. While increasing the Jahn-Teller coupling, one passes, from the region of parameters where the perturbation theory is applicable, through a complicated intermediate region, to a region where phonons, localized electrons and conduction electrons form a coherent state.4 pages, ReVTeX; Ref.[14] - correctedCondensed Mattertext