Equation of state and pressure induced amorphization of beta-boron from X-ray measurements up to 100 GPa.
The equation of state of boron has been measured up to 100 GPa by single-crystal x-ray diffraction with helium as the pressure transmitting medium. Rhombohedral beta-boron is the stable structure up to 100 GPa under hydrostatic conditions. Nonhydrostatic stress stabilizes a different rhombohedral structure. At about 100 GPa a pressure-induced amorphization is observed. The amorphous phase can be quenched to ambient pressure. An explanation is proposed based on the different stability under pressure between intraicosahedra and intericosahedra bonds.
Sanz
Delia Nieto
DN
European Synchrotron Radiation Facility, B.P. 220, F-38043 Grenoble, Cedex France.
Loubeyre
Paul
P
Mezouar
Mohamed
M