Modeling of structural transition of graphite into orthorhombic diamond-like phase

V. A. Greshnyakov, E. A. Belenkov

Chelyabinsk State University, Chelyabinsk, Russia

Abstract: Modeling of a phase transition of graphite into the orthorhombic diamond-like phase (called LA5) is carried out in the framework of density functional theory using the local density approximation. The calculations have shown that the structural transformation of graphite into the LA5 phase should occur at a pressure of 59.0 GPa. The value of the potential barrier separating the structural state, corresponding to the diamond-like LA5 phase, from the state, corresponding to graphite, is 0.15 eV/atom. A sufficiently large value of this potential barrier suggests the possibility of stable existence of the orthorhombic LA5 phase under normal conditions.

Keywords: diamond, diamond-like phase, phase transition, modeling.

UDC: 538.915