Application of Three-Dimensional Models

The first study of the PMF of two solutes in water-like particles by simulation methods was published by Geiger et al. (1979). A molecular dynamic simulation of 216 water-like particles and two neon -like solutes was carried out. Initially, the two solutes were placed at contact distance. During the evolution of the system, the two solute particles separated to a configuration of two cages, which is essentially a configuration such that the structure of water is not disrupted by the inclusion of the solute particles. The orientation of the water molecules around the solute was found to be such that no hydrogen bonding capability was lost. This is similar to the situation described in Fig. 4.41. 

Watanabe and Andersen (1986) carried out an extensive molecular dynamics simulation of aqueous solutions of krypton. They found that there is a stable configuration of the two solutes that corresponds to the water-separated distance between the two solutes. 

An extension of the molecular dynamics simulation to study aggregation of H0O solutes in water was carried out by Wallqvist (1991a,b). Rappaport and Scheraga (1982) found no evidence of aggregration of non-polar solutes in water-like solvent. Recently, Paschek (2004) carried out extensive molecular dynamics simulations of aqueous solutions using various models for water-like particles. 

Pangali et al. (1979a,b) calculated the PMF between two LJ solute particles (with ctss = 4.12 A and Sss/k = 170.1 K) in water-like particles by Monte Carlo simulation. They found a 

Ravishanker etal. (1982) extended the Monte Carlo simulation between two methane molecules in water-like particles. The results obtained by Ravishanker et al are quite different from those by Pangali et al., as well as those obtained by theoretical calculations by Pratt and Chandler (1977). The most striking difference is the occurrence of a second minimum at about 6 A, which corresponds to a configuration of a water-bridge between the two solutes rather than the water-separated configuration obtained by Pangali etal. (1979a,b) (Fig. 4.44). In my 

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