Structure and dynamics of water on the forsterite surface. Issue 44 (1st November 2018)

• Record Type: Journal Article
• Authors: Liu, Tingting; Gautam, Siddharth; Wang, Hsiu-Wen; Anovitz, Lawrence M.; Mamontov, Eugene; Allard, Lawrence F.; Cole, David R.
• Is Part Of: Physical chemistry chemical physics. Volume 20:Issue 44(2018)
• Page Start: 27822
• Page End: 27829
• Publication Date: 2018-11-01
• Subjects: Chemistry, Physical and theoretical -- Periodicals; 541.3
• DOI: 10.1039/c8cp05075a
• Languages: English
• ISSNs: 1463-9076

Abstract

Abstract : A combination of QENS experiments and MD simulations quantifies the structure and dynamics of water on the olivine surface. Abstract : The behavior of water on mineral surfaces is the key to understanding interfacial and chemical reaction processes. Olivine is one of the major rock-forming minerals and its interaction with water is a ubiquitous phenomenon both on Earth's surface and in the subsurface. This work presents a combined study using molecular dynamics (MD) simulations and quasi-elastic neutron scattering (QENS) experiments conducted using three different instruments to study the structure and dynamics of water on the forsterite (Mg-end member of olivine) surface at 270 K. A combination of three different QENS instruments probes dynamical processes occurring across a broad range of time scales (∼1 ps to ∼1 ns in this study). The water structure on the hydroxylated surface is composed of three distinct water layers, transitioning from well-ordered and nearly immobile closest to the surface to a less structured layer. The energies of three motions (including translation and rotation) derived from simulations agree well with the experiments, covering the energy range from a few to hundreds of micro electron volts.