Microscopic structure of water at elevated pressures and temperatures

• DOI: 10.1073/pnas.1220301110
• Publication Date: 2013-03-12T01:09:22Z
• Authors: Christoph J. Sahle; Christian Sternemann; Christian Schmidt; Susi Lehtola; Sandro Jahn; Laura Simonelli; Simo Huotari; Mikko Hakala; Tuomas Pylkkänen; Alexander Nyrow; Kolja Mende; Metin Tolan; Keijo Hämäläinen; Max Wilke
• Keywords: Atmospheric temperature range

We report on the microscopic structure of water at sub- and supercritical conditions studied using X-ray Raman spectroscopy, ab initio molecular dynamics simulations, density functional theory. Systematic changes in spectra with increasing pressure temperature are observed. Throughout thermodynamic range, experimental can be interpreted a structural model obtained from simulations. A spatial statistical analysis Ripley’s K-function shows that this is homogeneous nanometer length scale. According to distortions hydrogen-bond network increase dramatically when regime. In particular, average number hydrogen bonds per molecule decreases ≈0.6 600 °C p = 134 MPa.