Phase Diagram of Carbon Dioxide: Evidence for a New Associated Phase

Journal Article · Mon Jun 25 00:00:00 EDT 2001 · Physical Review Letters

DOI:https://doi.org/10.1103/PhysRevLett.86.5922· OSTI ID:40277917

Iota, Valentin; Yoo, Choong-Shik

The stability of CO{sub 2} phases has been investigated up to 50GPa and 750K by in situ Raman spectroscopy and visual observations using externally heated diamond-anvil cells. A new phase (CO{sub 2} -II) exists above 20GPa and 500K, which can be quenched to ambient temperature. The vibrational spectrum of this new CO{sub 2} polymorph suggests the dimeric pairing of molecules. Based on the present in situ data and previous laser-heating results, we present new constraints for the phase diagram of carbon dioxide to 50GPa and 2000K. We find that carbon dioxide exhibits dramatic changes, both in the molecular configuration and in the nature of intermolecular interaction at high pressures and temperatures.

• Research Organization: Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
• Sponsoring Organization: (US)
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 40277917
• Journal Information: Physical Review Letters, Vol. 86, Issue 26; Other Information: DOI: 10.1103/PhysRevLett.86.5922; Othernumber: PRLTAO000086000026005922000001; 013124PRL; PBD: 25 Jun 2001; ISSN 0031-9007
• Publisher: The American Physical Society
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
AMBIENT TEMPERATURE
CARBON DIOXIDE
CONFIGURATION
PHASE DIAGRAMS
RAMAN SPECTROSCOPY
STABILITY