FREEZING OF DIMERS ON A SQUARE LATTICE - A FINITE-SIZE-SCALING STUDY

We present a Monte Carlo study of a classical lattice-gas Hamiltonian formerly introduced by Parrinello and Tosatti in order to describe the coexistence of atomic and molecular phases. The nature of the orderin g transition undergone by the dense molecular fluid into a molecular-c rystal phase is investigated in two dimensions through phenomenologica l finite-size-scaling techniques.