II Simposio Internacional de Ciencia de los Materiales

THE ROLE OF CLAY CHARGE IN THE MOBILITY OF COMPENSATING CATIONS: AN APPROACH FROM MOLECULAR DYNAMICS

No programado

20m

Centro Demostrativo de Energía Renovables (Quinta de los Molinos)

Presentación oral Simulación de Materiales

Ponente

Sr. Carlos David Marrero Pérez (Zeolite Engineering Laboratory, Institute of Material Science and Technology (IMRE), University of Havana)

Descripción

The charge of clays plays an important role in the mobility of compensating cations and in swelling processes. In this work we have developed a method to generate Lithium Fluorhectorite (Li-Fh) clay models with a charge of -1.2e and a non-homogeneous charge distribution. This charge is closer to the experimentally reported value. We used this approach to study their interaction with water using Molecular Dynamics (MD) simulations. The MD simulations showed that the Li+ diffusion coefficient increases by two orders of magnitude with decreasing clay charge. Population analyses and Li+ coordination indicate a greater interaction of the cations with water molecules with decreasing clay charge, leading to a deformation in the stacking of clay layers in the 010 model. These results highlight the important influence of clay charge on cation dynamics and structural behaviour, providing insight into delamination and swelling mechanisms.

Key words: Molecular Dynamics Calculations, Diffusion in nanoscale solids, Computer modeling and simulation