High pressure raman spectroscopic study of low-cristobalite GaPO4

High-pressure Raman spectroscopic study of Fo90 hydrous wadsleyite

Raman spectra of monoclinic Fo90 hydrous wadsleyite with 2.4 wt% H2O have been measured in a diamond-anvil cell with helium as a pressure-transmitting medium to 58.4 GPa at room temperature. The most intense, characteristic wadsleyite modes, the Si–O– Si symmetric stretch at 721 cm 1 and the symmetric stretch of the SiO3 unit at 918 cm , shift continuously to 58.4 GPa showing no evidence of a f...

The High Pressure Behavior of Cristobalite

The most abundant rock-forming minerals in the eanh's crust are framework silicates with complex crystal structures. These materials displaya remarkable chemical and structUral diversity. In addition,~structUral phase transitions involving displacive distonions are panicularly common, leading to yet more structural variation. There have been suggestions that the distonive behavior of the framew...

1 High - pressure Raman spectroscopic studies of hydrous wadsleyite II

Pressure-induced polymerization of acrylic acid: a Raman spectroscopic study.

We report here the first in-situ Raman spectroscopic study of pressure-induced structural and polymeric transformations of acrylic acid. Two crystalline phases (I and II) were observed upon compression to approximately 0.3 and approximately 2.7 GPa. Phase I can be characterized with a single s-cis molecular conformation with possibly a similar structure to the low-temperature phase, while phase...

Pressure-induced transformations in diborane: a Raman spectroscopic study.

As a classical electron-deficient molecule with unique hydrogen bridge bonding, diborane has created considerable interest in the structural chemistry. We report here the first evidence of pressure-induced structural transformations of diborane probed by in situ Raman spectroscopy. At pressures around 4 GPa, diborane undergoes a liquid-solid phase transformation to a new high-pressure phase I w...