Séminaire Théorie

Mardi 12 Juin 2018 à 11h00.

Kinetic Monte Carlo approach as a hypothesis testing tool for tackling complex mineral-fluid reaction mechanisms

''Dissolution and growth of minerals in natural and man-made environments is a complex phenomenon involving large number of possible reactions taking place at mineral surfaces. We design Kinetic Monte Carlo models of the mineral dissolution processes by taking in account various controls of surface site reactivity, including short and long range neighbour orders, interfacial fluid structure, and all other details related to the crystal structure and chemistry. The simulations produce surface topographies and dissolution patterns as outputs, that can be directly compared to the experimental data. The design of the model and the values of the input parameters – molecular reaction rates derived from ab initio or Molecular Dynamics simulations – define the model output. Then the experimental data are used for model verification, and the modelling process is used as a tool to introduce and test work hypothesis regarding reaction mechanisms and the overall reactive system behaviour. This approached showed its effectiveness in relating molecular scale reaction mechanisms to the mineral-water interface reactive behaviour documented with microscopic techniques, e.g. Atomic Force Microscopy and Vertical Scanning Interferometry. References References: “Kinetic Monte Carlo Approach To Study Carbonate Dissolution”. Inna Kurganskaya and Andreas Luttge; Journal of Physical Chemistry C 2016, 120 (12), 6482–6492. “Variability of surface reactivity: What do we know?” Applied Geochemistry 2014, 132-157; Cornelius Fischer, Inna Kurganskaya, Thorsten Schafer and Andreas Luttge “Kinetic Monte Carlo simulations of silicate dissolution: Model complexity and parameterization” Journal of Physical Chemistry C (cover page), 2013, 117(47), 24894–24906; Inna Kurganskaya and Andreas Luttge. “A comprehensive stochastic model of phyllosilicate dissolution: Structure and kinematics of etch pits formed on muscovite basal face” Geochimica et Cosmochimica Acta, 120, 1 November 2013, 545-560; Inna Kurganskaya and Andreas Luttge “Does the stepwave model predict mica dissolution kinetics?”, Geochimica et Cosmochimica Acta, 2012, 97, 120-130; Inna Kurganskaya, Rolf S. Arvidson, Cornelius Fischer and Andreas Luttge “A Stochastic Treatment of Crystal Dissolution Kinetics” (2013), Andreas Luttge, Rolf S. Arvidson and Cornelius Fischer, Elements 9, 183-188''