Agrochemistry, Environmental, and Geochemistry

Complex Mineral Growth and Dissolution Reactions: Collaborative Experimental and Computational Perspectives (#225)

Many important geochemical reactions involve the growth and dissolution of minerals. While the description of these processes has been simplified historically, it is now understood that this approach fails to predict rates under many solution conditions, such as varying electrolyte or aqueous cation-to-anion ratio. This is because these reaction mechanisms are complex, e.g., multiple aqueous ionic species and surface sites are present and their relative importance changes with solution composition. Examples include nucleation versus advance/retreat of pre-existing monomolecular steps, clusters, and the effects of impurities. Many conventional conceptual models are being challenged by improved atomistic understanding, but as yet, process-based kinetics models built from individual reactions have had limited success, due in part to the difficulty of transitioning between scales. Successful development of process-based mineral growth and dissolution models requires a collaborative effort between modeling (both macroscopic, mesoscopic and atomistic), experiments, and measurements made in the field. In this session we will discuss current work being done to understand complex geochemical mineral surface reactions from either computational or experimental perspectives. New work highlighting understanding reaction mechanisms, atomic-level structure, kinetics, thermodynamics and upscaling of the mineral growth and dissolution processes themselves are encouraged, particularly collaborative work between modeling and experiments.
Last update: Dec 28, 2015