Water structure from scattering experiments and simulation

The progress which is measured in part by the reliability and reproducibility of the experimental scattering and simulation fields into the 21st century in the structural characterization of liquid water is presented. In addition, the progress in the simulation of liquid water structure is measured as well. Thus, it is important to emphasize that the quality of a water model or simulation should be judged more broadly than the structure it produces, or to consider the intended purpose of the model to decide if more severe approximations are warranted. This paper focuses exclusively on the structural properties obtained by the various theoretical modeling approaches, with the understanding that one water model or approach is not to be preferred over others based solely on better structural performance.