Morozov A. Monte Carlo simulations of orientational phase transitions in lattice systems of adsorbed molecules

The lattice systems of adsorbed molecules. An investigation of orientational phase transitions in the plane lattices of adsorbed molecules. Monte Carlo numerical simulation. The results obtained show that this system can exist in a new phase in which a preferred direction of long molecule axes arises in the absence of spontaneous polarization. The results of Monte Carlo simulation define a relation between the quasidipole Hamiltonian parameters for which the new phase can be observed experimentally. The critical temperatures were found for plane triangular dipole lattices with long-range interactions. Thermodynamical characteristics of phase transition in a CO monolayer on the NaCl(100) surface were simulated by the Monte Carlo method taking into account the quadrupole intermolecular potential.