The Minnesota Density Functionals and their Applications to Problems in Mineralogy and Geochemistry

Abstract

Quantum mechanical electronic structure calculations are playing an increasingly useful role in many areas of mineralogy and geochemistry. This review introduces the density functional method for such calculations, gives an overview of the density functionals developed at the University of Minnesota, and summarizes selected applications using these density functionals that are relevant to mineralogy and geochemistry. A key reason for the importance of computational methods in mineralogy is the ability to explore problems that cannot easily be studied in the laboratory. For example, it is very difficult to carry out laboratory studies under the real conditions of the Earth’s mantle and core because the temperature of the Earth’s core ranges up to 6000 K, and the pressure ranges up to 360 GPa. In the past decade, applications of quantum mechanical methods to understanding the properties of minerals and melts in the Earth’s interior have become increasingly important (Warren and Ackland 1996; Oganov and Brodholt 2000; Stixrude and Peacor 2002; Brodholt and Vocadlo 2006; Gillan et al. 2006; Tsuchiya et al. 2006). Some specific examples of problems in solid-state geochemistry where electronic structure calculations can be particularly useful are phase equilibria (Tsuchiya et al. 2004; Lay et al. 2005; Schwegler et al. 2008), equations of state, elastic constants, bulk and shear moduli (Li et al. 2006), hydrogen, proton, and water diffusion in minerals (Sakamura et al. 2003; Belonoshko et al. 2004; Pohlmann et al. 2004), the character and structural properties of hydroxyl groups in minerals and structures of hydrous minerals (Winkler et al. 1994, 1995; Nobes et al. 2000; Brodholt and Refson 2000; Churakov et al. 2003; Walker et al. 2006; Ockwig et al. 2009), hydrolysis and dissolution mechanisms (Strandh et al. 1997, Criscenti et …