### Session H36: Focus Session: Environment II: Green Processes

8:00 AM–11:00 AM, Tuesday, February 28, 2012
Room: 107C

Chair: Ilja Siepmann, University of Minnesota, Don Baer, Pacific Northwest Research Laboratory, and James Hutchinson, University of Oregon

Abstract ID: BAPS.2012.MAR.H36.8

### Abstract: H36.00008 : Hydrogen bond density and strength analysis on hydrated Rutile (110) and Cassiterite (110) surfaces

10:12 AM–10:24 AM

MathJax On | Off     Abstract

#### Authors:

Nitin Kumar
(Department of Physics, Penn State University)

Paul Kent
(Center for Nanophase Materials Sciences and Chemical Sciences Division, Oak Ridge National Laboratory)

Andrei Bandura
(St. Petersburg State University)

David Wesolowski
(Chemical Sciences Division, Oak Ridge National Laboratory)

James Kubicki
(Department of Geosciences, Penn State University)

Jorge Sofo
(Department of Physics, Penn State University)

We study the dynamics of water on the surface of cassiterite (110) and rutile (110) using ab-initio molecular dynamics simulation. Water adsorbs and dissociates on these surfaces. This dynamic equilibrium is dominated by the hydrogen bond (h-bond) network at the surface. The h-bond density analysis shows that adsorbed water molecules form higher average number of h-bonds on rutile ($\sim$2.3) as compared to the cassiterite surface ($\sim$2.1). On the other hand, bridging oxygen atoms form higher average number of h-bonds on cassiterite ($\sim$1.4) than rutile surface ($\sim$1.2). Dissociated species are found to have same average number of hydrogen bonds on both surfaces. As a consequence, the rutile surface has higher density of h-bonds at the surface than cassiterite, however, their strength is lower [N. Kumar et al., J. Chem. Phys. 134, 044706 (2011)]. This delicate balance is responsible for the different dynamical properties of both surfaces.

To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2012.MAR.H36.8