MSE 2016 - Full Program

Back to overview

Lecture

Water at solid/water interfaces: structure and spectroscopy

Tuesday (27.09.2016)
11:30 - 11:45
Part of:


At the solid/liquid interface water properties may be quite different from the bulk.

Here we use Density Functional Theory -based molecular dynamics simulations to describe

the water structure at mineral/water interfaces. Using a recently developed approach to calculate interface

vibrational spectra we are able to provide a molecular picture

of the interfacial water and a microscopic interpretation of the experiments.

In the case of the fluorite/water interface, our results show that, at low pH, the surface is positively charged,

causing a substantial degree of water ordering. The surface charge originates primarily from

the dissolution of fluoride ions, rather than from adsorption of protons to the surface.

At high pH we observe the presence of Ca-OH species pointing into the water.

These OH groups interact weakly with the surrounding water, and are responsible

for the “free OH” signature in the vibrational spectrum.

Speaker:
Dr. Marialore Sulpizi
Johannes Gutenberg University Mainz