2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/27627A Kondo model for three spin-one-half impurities placed at the vertices of an equilateral triangle is studied using the numerical renormalization-group method. The impurity spins can form two frustrated doublets which, because of the rotation symmetry, couple equally to the conduction band. Over a broad range of antiferromagnetic RKKY interaction strengths, this degeneracy drives the system to one of two novel, non-Fermi-liquid fixed points. Potential scattering is a relevant perturbation at one of these fixed points, but is marginal throughout the second regime.RevTex, 4 pages, 1 epsf-embedded EPS figureCondensed Mattertext