Abstract
In situ micro-Raman spectroscopy was performed on lanthanum borogermanate (LBG)glasses, compressed in a diamond anvil cell at ambient temperature. Up to 5.6 GPa thestructural changes are reversible, whereas experiments performed at 10 GPa and higher arecharacterized by hysteresis loops. A noticeable change of evolution of the main Raman band at800 cm−1 has been evidenced around 8 GPa. Indeed, at such a pressure, this Raman band is shifted inthe opposite direction while the pressure is still increasing. This change of slopes may bethe sign of a pressure-induced coordination number change. Upon decompression theRaman shift of this band follows a different path from the one during compression. Whenthe sample is returned to ambient pressure, it shows a shifted and lightly modified Ramanspectrum, suggesting that a new amorphous phase for LBG glass is reached under highpressure and still exists at atmospheric pressure. However, a comparison withLaBGeO5 crystals with the same composition shows that this material has a full elastic behaviour inthe same pressure range.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.