A grand ensemble Monte Carlo investigation of the Bell lattice model for water

Abstract
The lattice model for water, previously investigated by Bell using a Guggenheim-McGlashan first-order type of approximation (FOA), has been examined at three reduced temperatures T*=(kT/w)=0.2, 0.5 and 0.9 using grand ensemble Monte Carlo simulations. The parameters of the model are epsilon , w, u associated with first-neighbour energies, a hydrogen bond increment to this, and a 'penalty' incurred by molecules in triad sets on the two intertwined cubic ice lattices of the model. These parameters were given values suggested to be optimum by Bell ( epsilon /w=2.0, u/w=1.25). Results indicate that the cooperativity of the model is significantly underestimated by the FOA, although the general behaviour of the model is correctly represented. The authors have also made a preliminary examination of the possibility of introducing values of epsilon , w and u into the model which are directly related to H2O dimer potentials, rather than being estimated a posteriori from thermodynamic criteria. It is shown that this approach is feasible and that the advantage of extremely rapid calculation offered by the lattice model would not be lost.

This publication has 12 references indexed in Scilit: