Three-dimensional structure and hydrogen bonding of water in sub- and supercritical regions: a molecular simulation study

Molecular dynamics (MD) simulations of pure water in the sub- and supereritical regions were performed using a four-site flexible model (cm4P-mTR), which was recently proposed for study of water and aqueous solutions in liquid and critical region. MD simulation results show that this model is capable of reproducing the PVT behavior and self diffusion of water in the sub- and supercritical regions. An investigation of three-dimensional solution structure and hydrogen bonding (HB) of water via spatial distribution functions was performed. We found that besides water pairs in the linear hydrogen bonding (LHB), the HB network of water in supercritical region also consists of water pairs in the bifurcated hydrogen bonding (BHB) orientation.