PRESSURE INDUCED PHASES TRANSITIONS IN GaP: AN X RAY ABSORPTION SPECTROSCOPY INVESTIGATION

J. P. Itie , A. Polian (1) , C Jauberthie-Carillon , E Dartgge , A Fontaine , H Tolentino , G Tourillon

1 SU - Sorbonne Université

Brillouin scattering was used at room temperature to investigate the phase diagram of ammonia up to 20GPa. The results confirm the transition pressures liquid-solid III, solid III-solid IV and indicate a first order transformation around 15 GPa between solid IV and another solid named V. Using the sound velocity data below 1.2GPa, the refractive index is computed in liquid phase. In solid phase the refractive index is estimated through the Vedam model. This allows us to obtain the sound velocity and an effective elastic constant which is compared to the bulk modulus. Estimates of the elastic constants are given for the cubic phase III.

Domaines: Physique [physics]

J. P. Itie, A. Polian, C Jauberthie-Carillon, E Dartgge, A Fontaine, et al.. PRESSURE INDUCED PHASES TRANSITIONS IN GaP: AN X RAY ABSORPTION SPECTROSCOPY INVESTIGATION. Physica B: Condensed Matter, 1989. ⟨hal-03059437⟩