Water is arguably the most important material on earth. Despite the simple structure of water molecule in gas phase, the molecular structure of liquid water its condensed phase has posed a great challenge to the scientists. Controversy concerning the nature of H-bond network is present not only in the theoretical simulation from first principles but also the experimental interpretation based on probes such as core-level X-ray spectroscopy and neutron or X-ray diffraction. We demonstrate that a fully ab initio approach, relying on density functional approximations higher on Jacob’s ladder, provides such an accurate description of water as well as the ions solvated in water such as the proton transfer effect. In the above, the inclusions of the long-range van der Waals interactions and mitigation of self-interaction error in the state-of-art density functional approximations are indispensable.

Xifan Wu finished his BS degree in Physics Department of Nanjing University. In Fall 2006, he obtained the PhD degree in Physics under supervision of Prof. David Vanderbilt at Rutgers University. He has been a Postdoc Research Associate supervised by Prof. Roberto Car in Chemistry Department of Princeton University from 2006-2010. In Fall 2010, Xifan Wu joined the Physics Department of Temple University as a tenure track Assistant Professor. He was tenured and promoted to be an Associate Professor in Physics since summer 2016. Xifan Wu is supported by National Science Foundation CAREER award since 2016.