title: Phase diagram of trivalent and pentavalent patchy particles.
abstract: We compute the equilibrium phase diagram of two simple models for patchy particles with three and five patches in a very broad range of pressure and temperature. The phase diagram presents low-density crystal structures which compete with the fluid phase. The phase diagram of the five-patch model shows re-entrant melting, in analogy with the previously studied four-patch case, a metastable gas-liquid critical point and a stable, high-density liquid. The three-patch model shows a stable gas-liquid critical point and, in the region of temperatures where equilibration is numerically feasible, a stable liquid phase, suggesting the possibility that in this small valence model the liquid retains its thermodynamic stability down to the vanishing range limit.
authors.affiliation: Dipartimento di Fisica, Sapienza-Università di Roma, Piazzale Aldo Moro 5, 00185 Roma, Italy.
authors.forename: Flavio
authors.initials: F
authors.lastname: Romano
authors.forename: Eduardo
authors.initials: E
authors.lastname: Sanz
authors.forename: Piero
authors.initials: P
authors.lastname: Tartaglia
authors.forename: Francesco
authors.initials: F
authors.lastname: Sciortino