Reaction Mechanisms and Solid–Gas Phase Reactions: Theory and Density Functional Theory Simulations

Geochemistry was dominated by thermodynamic theory for much of its first century of existence (Anderson and Crerar 1993; Nordstrum 2006). Interest in high temperature igneous and metamorphic processes combined with the presumption of long time periods that are available for geochemical reactions justified the assumption of equilibrium thermodynamics. Consequently, geochemists were interested in reactants and products, i.e., examining A, B, and C in reactions like A + B → C without concern for what happens in between as represented by the arrow. In fact, for many geochemical reactions, the reactants and products can be treated as components...