title: Observation of a pressure-induced first-order polyamorphic transition in a chalcogenide glass at ambient temperature.
abstract: An apparently first-order polyamorphic transition has been observed with increasing pressure at ambient temperature in a molecular glass of composition Ge(2.5)As(51.25)S(46.25) Raman spectroscopic measurements on pressure-quenched samples and in situ x-ray diffraction measurements indicate that this transition corresponds to a collapse of the ambient-pressure molecular phase to a high-pressure network phase. The high-pressure phase first appears at a pressure of approximately 8-9 GPa and the transformation becomes complete at approximately 14-15 GPa. Calorimetric measurements indicate that the low- and high-pressure phases are thermodynamically distinct and that they coexist in the transition range.
authors.affiliation: Department of Chemical Engineering and Materials Science, University of California, Davis, 95616, USA.
authors.forename: S
authors.initials: S
authors.lastname: Sen
authors.forename: S
authors.initials: S
authors.lastname: Gaudio
authors.forename: B G
authors.initials: BG
authors.lastname: Aitken
authors.forename: C E
authors.initials: CE
authors.lastname: Lesher