STRUCTURE AND REACTIVITY OF SEMICONDUCTING MINERAL SURFACES: CONVERGENCE OF MOLECULAR MODELING AND EXPERIMENT

Abstract

Semiconducting minerals are a unique class of materials that have a broad range of influence in near-surface geochemical environments. Many are electroactive and play an important role as natural solid phase electron sources and sinks. This property gives them the capacity to control the availability of electrons in the environment, with direct and indirect effects on many redox-based geochemical and biogeochemical processes. Examples include the natural cycling of redox-active elements (Calmano et al. 1994; Nimick and Moore 1994), dissimilatory metal reduction in microbial respiration (Lovley and Phillips 1988; Lovley et al. 1991), the oxidative...