title: Pressure-induced sharp coordination change in liquid germanate.
abstract: Local structures around germanium in liquid germanate have been investigated by means of in situ x-ray absorption measurements up to 9 GPa at 1273 K. Liquid germanate consisting of tetrahedrally coordinated germanium contracts with increasing pressure without significant changes in the local structure up to 2.5 GPa and then shows an abrupt fourfold-to-sixfold coordination change around 3 GPa. The coordination change is completed below 4 GPa where upon a high-density liquid consisting of octahedrally coordinated germanium becomes stable. The GeO6 octahedron in the high-density liquid is more compressible than that in solids.
authors.affiliation: Department of Earth and Space Science, Osaka University, Toyonaka, Osaka 560-0043, Japan. ohtaka@ess.sci.osaka-u.ac.jp
authors.forename: Osamu
authors.initials: O
authors.lastname: Ohtaka
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Arima
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Fukui
authors.forename: Wataru
authors.initials: W
authors.lastname: Utsumi
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Katayama
authors.forename: Akira
authors.initials: A
authors.lastname: Yoshiasa