Monte Carlo simulations have been performed in NVT ensemble, in order to study structural and thermodynamic properties of 2D Mercedes-Benz water model. We studied properties of the model at different temperatures and densities. The model that has been used, allows independent varying of rotational and translational temperature. We were interested in effect of separated rotational and translational temperature on both structural and thermodynamic properties of system of MB particles at constant pressure. To obtain information on properties of the system at constant pressure, results from NVT simulations have been interpolated on constant pressure 0,12. Increase in density of system at constant temperature (rotational and translational) reduces effect of hydrogen bonds between particles, as result structure of the system becomes less ordered. At constant density the effect of all interactions between particles weakens with increasing temperature (in this case rotational and translational temperature are equal), while the effect of temperature on hydrogen bonds is greater than effect on van der Waals interactions. In case of constant pressure, increase in rotational temperature causes decrease in quantity of hydrogen bonds in the system, but it doesn’t affect van der Waals interaction. However increase in translational temperature diminishes effect of hydrogen bonda on the system as well as van der Waals interactions, yet the effect on hydrogen bonds is greater. It was also investigated how average excess energy of particle, density, excess heat capacity and excess chemical potential changes with changes in translational and rotational temperature at constant pressure. At low rotational and translational temperature some of thermodynamic quantities possess local extrema. High rotational temperature diminishes distinctness of anomalous properties of thermodynamic quantities, which are consequence of hydrogen bonds, as result the system becomes more normal liquid like.
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