Experimental evidence for a high-pressure isostructural phase transition in osmium |
| |
Authors: | Occelli Florent Farber Daniel L Badro James Aracne Chantel M Teter David M Hanfland Michael Canny Bernard Couzinet Bernard |
| |
Affiliation: | Earth Science Division and IGPP, Lawrence Livermore National Laboratory, USA. |
| |
Abstract: | We have measured the isothermal equation of state (EOS) of osmium to 75 GPa under hydrostatic conditions at room temperature using angle-dispersive x-ray diffraction. A least-squares fit of this data using a third-order Birch-Murnaghan EOS yields an isothermal bulk modulus K0=411+/-6 GPa, showing osmium is more compressible than diamond. Most importantly, we have documented an anomaly in the compressibility around 25 GPa associated with a discontinuity in the first pressure derivative of the c/a ratio. This discontinuity plausibly arises from the collapse of the small hole-ellipsoid in the Fermi surface near the L point. |
| |
Keywords: | |
本文献已被 PubMed 等数据库收录! |
|