  We study the phase diagram of a binary mixture of patchy particles which has
been designed to form a reversible gel. For this we perform Monte Carlo and
molecular dynamics simulations to investigate the thermodynamics of such a
system and compare our numerical results with predictions based on the
analytical parameter-free Wertheim theory. We explore a wide range of the
temperature-density-composition space that defines the three-dimensional phase
diagram of the system. As a result, we delimit the region of thermodynamic
stability of the fluid. We find that for a large region of the phase diagram
the Wertheim theory is able to give a quantitative description of the system.
For higher densities our simulations show that the system is crystallizing into
a BCC structure. Finally we study the relaxation dynamics of the system by
means of the density and temperature dependences of the diffusion coefficient.
We show that there exists a density range where the system passes reversibly
from a gel to a fluid upon both heating and cooling, encountering neither
demixing nor phase separation.
