Pressure-Induced Structure Transitions in Eu Metal to 92 GPa

Autor: Bi, W., Meng, Y., Kumar, R. S., Cornelius, A. L., Tipton, W. W., Hennig, R. G., Zhang, Y., Chen, C., Schilling, J. S.
Rok vydání: 2010
Předmět:
Zdroj: Phys. Rev. B 83, 104106 (2011)
Druh dokumentu: Working Paper
DOI: 10.1103/PhysRevB.83.104106
Popis: Synchrotron x-ray diffraction experiments have been carried out on Eu metal at ambient temperature to pressures as high as 92 GPa (0.92 Mbar). Following the well-known bcc-to-hcp transition at 12 GPa, a mixed phase region is observed from 18 to 66 GPa until finally a single orthorhombic (Pnma) phase persists from 66 to 92 GPa. These results are compared to predictions from density functional theory calculations. Under pressure the relatively large molar volume Vmol of divalent Eu is rapidly diminished, equaling or falling below Vmol(P) for neighboring trivalent lanthanides above 15 GPa. The present results suggest that above 15 GPa Eu is neither divalent nor fully trivalent to pressures as high as 92 GPa.
Databáze: arXiv