  Values of the fifth virial coefficient, compressibility factors, and
fluid-fluid coexistence curves of binary asymmetric nonadditive mixtures of
hard disks are reported. The former correspond to a wide range of size ratios
and positive nonadditivities and have been obtained through a standard Monte
Carlo method for the computation of the corresponding cluster integrals. The
compressibility factors as functions of density, derived from canonical Monte
Carlo simulations, have been obtained for two values of the size ratio ($q=0.4$
and $q=0.5$), a value of the nonadditivity parameter $\Delta=0.3$), and five
values of the mole fraction of the species with the biggest diameter
($x_1=0.1$, $0.3$, $0.5$, $0.7$, and $0.9$). Some points of the coexistence
line relative to the fluid-fluid phase transition for the same values of the
size ratios and nonadditivity parameter have been obtained from Gibbs Ensemble
Monte Carlo simulations. A comparison is made between the numerical results and
those that follow from some theoretical equations of state.
