Water structure in the interfoliar space of smectites

***Water structure in the interfoliar space of smectites : Crystal-chemical constraints and dynamic implications.

Duration : 2012 - 2013
Contact at ISTerre : Bruno Lanson
ISTerre team involved : Mineralogy and Environments
Origin of funding : CNRS interdisciplinary program - Needs Challenge (Nuclear, energy, environment, waste, society)
Collaborations : ISTerre (Bruno Lanson, Baptiste Dazas, Fabrice Brunet), IC2MP (Poitiers ; Eric Ferrage), IMCMP (Paris, Jean-Louis Robert).

**Summary

The crystallochemical but also dynamic characterization of water in the interfoliate spaces of hydrated phyllosilicates (smectites) is essential for the determination of the geometric and dynamic properties of waste containment barriers (bentonites) as a whole, but also for the mobility of contaminants for which water will be the main vector.

The work envisaged consists in taking into account the effect of several structural parameters (presence of structural fluorine, quantity and location of leaf load in particular) on the structure and dynamics of interfoliate water in these minerals.

The ultimate objective is to predict the reactivity of these minerals in the environment on the basis of a limited number of crystallochemical parameters but also to determine the relevance of the fluorinated analogues commonly used to constrain water dynamics in these confined spaces.

Publications
Baptiste Dazas, Bruno Lanson, Josef Breu, Jean-Louis Robert, Manuel Pelletier & Eric Ferrage (soumis) Smectite fluorination and its impact on interlayer water content and structure : A way to fine tune the hydrophilicity of clay surfaces ? Soumis à Microporous And Mesoporous Materials.