2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/164512Using numerical techniques and asymptotic expansions we obtain the phase diagram of a paradigmatic model of Coulomb frustrated phase separation in systems with negative short-range compressibility. The transition from the homogeneous phase to the inhomogeneous phase is generically first order in isotropic three-dimensional systems except for a critical point. Close to the critical point, inhomogeneities are predicted to form a BCC lattice with subsequent transitions to a triangular lattice of rods and a layered structure. Inclusion of a strong anisotropy allows for second- and first-order transition lines joined by a tricritical point.4 pages, 3 figures. Improved figures and presentationStrongly Correlated ElectronsMaterials ScienceSoft Condensed Mattertext