Computer Simulations of Simple Liquids

Two types of reference fluids have been studied extensively by computer experiments. One system is composed of the non-interacting hard spheres discussed 

and T are held constant. In this way, the configurational integral Z is calculated. This immediately allows one to calculate the partition function Q for the ensemble (equation (2.2.31)) and thus the thermodynamic functions for the system. In addition, the pair correlation function for the fiuid is obtained in this calculation. 

The acceptance or rejection of configurations with high potential energy is a special feature of modern Monte Carlo techniques [20, 21]. In the case of hard-sphere systems, this choice is particularly simple because U is equal to zero when spheres do not overlap, and infinity when they do. Details about application of this technique to more complex systems such as molecular fiuids involve some variations which are described in the original literature. 

The results of computer experiments are often used to test approximate theories of liquids such as those based on the OZ equation discussed above. For this reason they are an important part of understanding the structure of liquids and how structure affects liquid properties. 

8 Estimation of Thermodynamic Properties from the Pair Correlation Function 

---

M. P. TUien and D. J. Tildesley. Computer Simulation of Simple Liquids, Clarendon Press, Oxford, UK, 1987. 

---