Universal transition state for high-pressure zinc blende to rocksalt phase transitions.

First-principles density functional calculations show that the high-pressure transitions of different semiconductors from zinc blende to rocksalt go through a transition state, which is universal in the sense that its position along the path and the corresponding geometry is independent of the chemical components of the semiconductor. This is explained using a Landau-like model expansion of the free energy in cosine functions of atomic position.