Hexafluorobenzene under extreme conditions

Journal Article · 23 February 2016 · Journal of Physical Chemistry. B, Condensed Matter, Materials, Surfaces, Interfaces and Biophysical Chemistry

DOI: https://doi.org/10.1021/acs.jpcb.6b00497 · OSTI ID:1332632

Pravica, Michael ^[1]; Sneed, Daniel ^[2]; Wang, Yonggang ^[2]; Smith, Quinlan ^[2]; White, Melanie ^[2]

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1. Univ. of Nevada, Las Vegas, NV (United States); University of Nevada, Las Vegas
2. Univ. of Nevada, Las Vegas, NV (United States)

Here, we report the results from three high pressure expts. on hexafluorobenzene (C₆F₆). In the first expt., Raman spectra were recorded up to 34.4 GPa. A phase transition from I → II was obsd. near 2 GPa. Near 8.8 GPa, a phase transition to an unreported phase (III) commenced. Above 20.6 GPa, yet another phase was obsd. (IV). Pressure cycling was employed to det. that, below 25.6 GPa, all pressure-induced alterations were reversible. However, at pressures above 20 GPa, dramatic spectral changes and broadening were obsd. at 25.6 and 34.4 GPa. The sample irreversibly changed into a soft solid with waxlike consistency when pressure was reduced to ambient and was recoverable. In the second expt., IR spectra were collected up to 14.6 GPa. The phase transition (II → III) near 8.8 GPa was confirmed. An angular dispersive X-ray diffraction expt. was conducted to 25.6 GPa. Phase transitions above 1.4 GPa (I → II), above 5.5 GPa (II → III), above 10 GPa (III → IV), and above 15.5 GPa (IV → V) were obsd. Near 25.6 GPa long-range cryst. order was lost as the X-ray diffraction spectrum presented evidence of an amorphous solid.

• Research Organization: Univ. of Nevada, Las Vegas, NV (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA); USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
• Grant/Contract Number: NA0001982
• OSTI ID: 1332632
• Journal Information: Journal of Physical Chemistry. B, Condensed Matter, Materials, Surfaces, Interfaces and Biophysical Chemistry, Journal Name: Journal of Physical Chemistry. B, Condensed Matter, Materials, Surfaces, Interfaces and Biophysical Chemistry Journal Issue: 10 Vol. 120; ISSN 1520-6106
• Publisher: American Chemical SocietyCopyright Statement
• Country of Publication: United States
• Language: English