Using my own computer program for Monte Carlo simulation in NpT ensemble, I explored structural and thermodynamic properties of a simple two-dimensional single-point water model. A single angular degree of freedom, describing the hydrogen bonding between two water molecules, is accounted for through sinusoidal rose curves. A 3-petal curve of the general form sin(3θ) was used and the model was therefore named rose water. Compared to its analogue, i.e. a four-site 2D Mercedes Benz (MB) model, the rose water is computationally more efficient due to the resulting decrease in the number of pairwise interaction sites between neighbouring waters. Proper selection of model’s potential parameters gives good agreement with the MB water model: it is structurally similar to MB water and exhibits qualitatively same water-like anomalous behaviour. The work will present the effect of model’s parameters and temperature on pair distribution function, as well as temperature dependence of density, isothermal compressibility, coefficient of thermal expansion, and heat capacity. Selected thermodynamic properties and pair distribution function will be compared to the results of MB model for various temperatures.
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