As water is the most important substance we use, we want to describe its properties as best we can. That is problematic, because water is an anomalous liquid. There are a lot of different water models, which have different strengths and weaknesses. In this work simple rigid point charge models are presented, which are commonly used to calculate quantitative properties. Methods for their use in molecular dynamics are described and used for creation of our own program. It is used to calculate basic thermodynamic quantities (temperature, pressure, density, potential energy) for 5 different models (SPC, SPC/E, TIP4P, TIP4P-Ew, TIP4P/2005) and radial distribution functions and 4 different thermodynamic properties (isothermal compressibility, thermal expansion coefficient and 2 heat capacities) for SPC/E and TIP4P/2005 models.
|
