2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/156771The electron-electron interactions effects on the shape of the Fermi surface of doped graphene are investigated. The actual discrete nature of the lattice is fully taken into account. A $π$-band tight-binding model, with nearest-neighbor hopping integrals, is considered. We calculate the self-energy corrections at zero temperature. Long and short range Coulomb interactions are included. The exchange self-energy corrections for graphene preserve the trigonal warping of the Fermi surface topology, although rounding the triangular shape. The band velocity is renormalized to higher value. Corrections induced by a local Coulomb interaction, calculated by second order perturbation theory, do deform anisotropically the Fermi surface shape. Results are compared to experimental observations and to other theoretical results.10 pages, 6 figuresStrongly Correlated ElectronsMesoscale and Nanoscale Physicstext