Using ab initio molecular dynamics we study pressure-induced hydrogen sublattice amorphization in Mg(OH)2 and Ca(OH)2. Our calculations reproduce the experimental behavior of these two systems, with Ca(OH)2 showing significantly more marked effects. We find that the interplay of short-range repulsion and electrostatic forces explains the amorphization process. This is due to a frustration phenomenon and has a dynamical character at room temperature, but it can be frozen in at low temperatures.
ASJC Scopus subject areas
- Physics and Astronomy(all)