Novel pressure-induced phase transformations in hydrous layered materials
Journal
Geophysical Research Letters
Journal Volume
29
Journal Volume
29
Journal Issue
16
Journal Issue
16
Start Page
17-1
End Page
17-4
ISSN
00948276
Date Issued
2002-08-15
Author(s)
Abstract
High-pressure Raman and X-ray diffraction data on single crystals of hydrous layer-structure minerals, dickite and gibbsite, reveal structural phase transitions occuring between 2.0 and 2.5 GPa. In the case of dickite, this is the first documented occurence of a pressure-induced phase transformation in a 1:1 phyllosilicate. Above the transition the structure of individual 1:1 layers remains unchanged, whereas the stacking of individual layers and the interlayer topology change significantly. Similar to dickite, single-crystal Raman spectra of gibbsite show large perturbations in the v(OH) region and suggest that the interlayer OH groups play a critical role in the phase transformation.
Publisher
American Geophysical Union
Type
journal article