Temperature-dependent structure of liquid water investigated by means of energy-dispersive x-ray diffraction and molecular dynamics simulations.

X-ray diffraction is investigated in the supercooled region (263-273 K) and, for comparison, at ambient conditions. By means of an energy-dispersive set-up coherent x-ray scattering cross sections within a wide range of momentum transfer values are monitored simultaneously using in-house laboratory equipment. The data are corrected for the energy-dependent detector response, geometric broadening effects, sample absorption and Compton scattering. The corrected diffraction curves are in good agreement with results from the Advanced Light Source (ALS). Additional comparisons with available literature data and with computer simulation results of different rigid water models are presented, relating the scattering intensities to the microscopic H-bond structure and dynamics.