Heat capacity of water; Path integral molecular dynamics approach

Shiga, Motoyuki   

In general, quantitative estimation of heat capacity has been a difficult but an important issue in molecular simulation. This is because heat capacity involves quantum mechanics of atomic motions, particularly at the low temperature range. One of the useful approaches to such quantum systems is path integral simulation method. However, heat capacity, which is the dispersion of energy, is so computationally demanding that it was not feasible until the recent development of parallel computers and efficient algorithms. In this paper, we introduce a path integral molecular dynamics approach for the estimation of heat capacities, and apply this technique to three states of water.