Post-stishovite transition in hydrous aluminous SiO2

摘要: Abstract Lakshtanov et al. (2007) showed that incorporation of aluminum and some water into SiO2 significantly reduces the post-stishovite transition pressure in SiO2. This discovery suggested ferroelastic subducted MORB crust could be source reflectors/scatterers with low shear velocities observed mid to upper lower mantle. A few years later, a similar effect was anhydrous Al-bearing silica. In this paper, we show by first principles static calculations molecular dynamics using inter-atomic potentials hydrogen bonds mobility play crucial role lowering pressure. cooperative redistribution atoms is main mechanism responsible for reduction hydrous aluminous stishovite. The enhanced increasing concentration. perspective suggests potential relationship between depth seismic scatterers content