2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/218752We study the repulsive Hubbard model both analytically and numerically on a family of highly frustrated lattices which have one-electron states localized on isolated trapping cells. We construct and count exact many-electron ground states for a wide range of electron densities and obtain closed-form expressions for the low-temperature thermodynamic quantities. Furthermore, we find that saturated ferromagnetism is obtained only for sufficiently high electron densities and large Hubbard repulsion $U$ while there is no finite average moment in the ground states at lower densities.8 pages, 7 figures, accepted for publication in Phys. Rev. BStrongly Correlated Electronstext