2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/29915We study the possibility of existence of bound states for two interacting He-4 atoms. It is shown that for some potentials, there exist not only discrete levels but also bands akin to those in the Kronig--Penney model.5 pages, LATEX2e, 3 EPS figuresSoft Condensed Mattertext