Lindeman's criterion: diamond graphitization temperature and its   dependence on external pressure
  A simple model for the "diamond graphitization" type of phase transition is proposed, leading to a good agreement with the experimental data. The phase transition temperature dependence on the external pressure is found. A new phenomenon in diamond is predicted, which is a decrease of the temperature of graphitization with increase of external pressure. 
V.N. Strekalov
cond-mat.mtrl-sci cond-mat.other quant-ph