X-ray shines light on the water mystery

Note: Special Seminar, Monday, Feb. 22 Pizza served at 11:45 AM
Speaker: Anders Nilsson, Stanford Institute for Materials and Energy Sciences, SLAC National Accellerator Laboratory and Stockholm University, Sweden

When: February 22, 2010 (Mon), 12:00PM to 01:00PM (add to my calendar)
Location: SCI 352
Hosted by: H. Eugene Stanley

This event is part of the Biophysics/Condensed Matter Seminar Series.

Abstract:
Water is the key compound for our existence on this planet and it is involved in many important physical, chemical, biological and geological processes. Although water is the most common molecular substance it is also most unusual with many anomalies in its thermodynamic properties such as compressibility, density variation and heat capacity. The question of the structure of the hydrogen bonding network in water has been discussed intensively for over 100 years and has not yet been resolved. This talk will describe recent x-ray spectroscopy and scattering measurements showing that the liquid can be described as fluctuations between two types of local hydrogen bonded structures driven by incommensurate requirements for minimizing enthalpy and maximizing entropy. The connection of these results to low and high density water and the 2nd critical point model will be discussed.