Spectroscopic Studies of Cyclopentane under Extreme Conditions and Implications for the P-T Phase Diagram

POSTER

Abstract

Infrared (IR) spectroscopy and Raman scattering combined with diamond anvil cell (DAC) and cryogenic techniques have been employed to investigate cyclopentane up to 4 GPa in the temperature range of 100-350 K and isothermal compression up to 84 GPa at room temperature. Four phases including liquid, plastic phases I and II, and truly crystalline phase III are clearly identified in the P-T range studied based on the changes of the ring breathing mode and CH$_{2}$ rocking modes. The phase diagram is extended to the pressure and temperature range of 0 -- 4.0 GPa and 105 -- 350 K. Further compression at room temperature up to 84 GPa, another high-pressure phase (IV) is observed based on the appearance of low frequency peaks related to the lattice vibrational modes in the synchrotron far-IR spectra. The spectroscopic results indicate that cyclopentane persists the orientation ordered crystalline phase up to 84 GPa at room temperature.

Authors

  • Chunli Ma

    Geophysical Laboratory, Carnegie Institution of Washington, 5251 Broad Branch Road NW, Washington D.C. 20015, USA, Jilin University, PR China, Jilin University

  • Zhenxian Liu

    Geophysical Laboratory, Carnegie Institution of Washington, Brookhaven National Laboratory, Geophysical Laboratory, Carnegie Institution of Washington, 5251 Broad Branch Road NW, Washington D.C. 20015, USA, Carnegie Institution of Washington

  • Qiliang Cui

    State Key Laboratory of Superhard Materials, Jilin University, Changchun 130012, China, Jilin University, PR China, Jilin University

  • Russel Hemley

    Geophysical Laboratory, Washington, DC, USA, Geophysical Laboratory, Carnegie Institution of Washington, Geophysical Laboratory, Carnegie Institution of Washington, 5251 Broad Branch Road NW, Washington D.C. 20015, USA, Carnegie Institution for Science