X-ray induced mobility of molecular oxygen at extreme conditions

Journal Article · Mon Nov 25 00:00:00 EST 2013 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4836475· OSTI ID:22217839

Pravica, Michael; Sneed, Daniel; Guardala, Griffin; Smith, Quinlan ^[1]; Popov, Dmitry; Sinogeikin, Stanislav ^[2]

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1. High Pressure Science and Engineering Center (HiPSEC) and Department of Physics, University of Nevada Las Vegas (UNLV), Las Vegas, Nevada 89154-4002 (United States)
2. HPCAT, Geophysical Laboratory, Carnegie Institution of Washington, 9700 South Cass Ave., Argonne, Illinois 60437 (United States)

We report an in situ Raman study of KClO{sub 4} irradiated with x-rays in a diamond anvil cell. Decomposition via KClO{sub 4} + hv → KCl + 2O{sub 2} was monitored via the O{sub 2} vibron at 2 GPa, 6 GPa, and 9 GPa. For all pressures, the vibron grew in intensity and then diminished after successive irradiation suggesting that O{sub 2} was diffusing away from the irradiated region. Surprisingly, the diffusion rate accelerated with pressure increase, indicating that the nonhydrostatic pressure gradient was likely driving molecular diffusion of oxygen. At 9 GPa, the vibron bifurcated suggesting that O{sub 2} exists as two forms: interstitial and bulk solid. This method can be employed to study molecular diffusion under extreme conditions.

• OSTI ID: 22217839
• Journal Information: Applied Physics Letters, Vol. 103, Issue 22; Other Information: (c) 2013 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
DECOMPOSITION
DIAMONDS
DIFFUSION
INTERSTITIALS
IRRADIATION
MOBILITY
OXYGEN
POTASSIUM CHLORIDES
POTASSIUM PERCHLORATES
PRESSURE GRADIENTS
PRESSURE RANGE GIGA PA
RAMAN SPECTRA
SOLIDS
X RADIATION