The structure of liquid water explained by a two-state model

Structural studies of liquid water have been carried out for some time. However, no model has emerged that fiiUy explains all the currently known features present. The radial-distribution function (RDF) or the closely related pair-correlation fimction (PCF), used as interpretive tools for local structure, are known to be both pressure and ten:^)erature sensitive, indicating that the local structure of liquid water changes as a function of these two variables. This would be expectod. However, it is the details and subtleties of these structural changes that have not had an understanding. In this thesis, it is shown how non-hydrogen-bonded second neighbor consklerations can be used to explain these structural changes. By use of an outer structure two-state model, which has been successfiil in explaining all the anomalies of water, the detailed features of the structure fimctions and their sensitivity to temperature and pressure can be reproduced. In particular, the isochoric temperature differential (ITD) x-ray scattering results of Bosio, Chen and Tebceira, as well as the pressure X-ray work of Okhulkov and the pressure neutron work of Soper, emerge from the analysis, giving new insights into the experiments.