The experimental compression behavior of platinum hydride to 128 GPa

Abstract

To date, the exact structure of PtH, the key to resolve the controversial hexagonal close-packed (hcp) phase of SiH4, is still absent above 100 GPa. Therefore, PtH has been synthesized and its compression behavior is determined through the angle dispersive X-ray diffraction method. We find that hcp PtH keeps stable up to at least 128 GPa and its experimental lattice parameters are highly consistent with those of the hcp one in the SiH4 experiment. The present results provide reliable experimental information of PtH under high pressure, and directly clarify the debate between hcp PtH and “SiH4”.