Fluorine chemistry at extreme conditions: Possible synthesis of $HgF_4$

  • Michael G. Pravica Department of Physics and Astronomy University of Nevada, Las Vegas
  • Sarah Schyck High Pressure Science and Engineering Center (HiPSEC) and Department of Physics, University of Nevada Las Vegas (UNLV), 89154-4002 Las Vegas, Nevada, USA.
  • Blake Harris High Pressure Science and Engineering Center (HiPSEC) and Department of Physics, University of Nevada Las Vegas (UNLV), 89154-4002 Las Vegas, Nevada, USA.
  • Petrika Cifligu High Pressure Science and Engineering Center (HiPSEC) and Department of Physics, University of Nevada Las Vegas (UNLV), 89154-4002 Las Vegas, Nevada, USA.
  • Eunja Kim High Pressure Science and Engineering Center (HiPSEC) and Department of Physics, University of Nevada Las Vegas (UNLV), 89154-4002 Las Vegas, Nevada, USA.
  • Brant Billinghurst Far-IR beamline, Canadian Light Source, 44 Innovation Blvd, Saskatoon, SK S7N 2V3, Canada.
Keywords: fluorine chemistry at extreme conditions, mercury transition metal behavior, diamond anvil cell, high pressure, infrared spectroscopy, x-ray photochemistry

Abstract

By irradiating a pressurized mixture of a fluorine-bearing compound ($XeF_2$) and $HgF_2$ with synchrotron hard x-rays (>7 keV) inside a diamond anvil cell, we have observed dramatic changes in the far-infrared spectrum within the 30-35 GPa pressure range which suggest that we may have formed $HgF_4$ in the following way: $XeF_2 \xrightarrow{hv} Xe + F_2$ (photochemically) and $HgF_2 + F_2 \rightarrow HgF_4$ (30 GPa < P < 35 GPa). This lends credence to recent theoretical calculations by Botana et al. that suggest that Hg may behave as a transition metal at high pressure in an environment with an excess of molecular fluorine. The spectral changes were observed to be reversible during pressure cycling above and below the above mentioned pressure range until a certain point when we suspect that molecular fluorine diffused out of the sample at lower pressure. Upon pressure release, $HgF_2$ and trace $XeF_2$ were observed to be remaining in the sample chamber suggesting that much of the $Xe$ and $F_2$ diffused and leaked out from the sample chamber.

 

Received: 29 October 2018,  Accepted: 18 January 2019; Edited by: A. Goñi, A. Cantarero, J. S. Reparaz; DOI: http://dx.doi.org/10.4279/PIP.110001

Cite as: M Pravica, S Schyck, B Harris, P Cifligu, E Kim, B Billinghurst, Papers in Physics 11, 110001 (2019).

This paper, by M Pravica, S Schyck, B Harris, P Cifligu, E Kim, B Billinghurst, is licensed under the Creative Commons Attribution License 4.0.

 

Author Biography

Michael G. Pravica, Department of Physics and Astronomy University of Nevada, Las Vegas
I am a professsor of physics at the University of Nevada Las Vegas,  I study matter subjected to extreme conditions and am developing useful hard x-ray photochemistry. I earned my doctorate and masters degrees at Harvard university and my B.Sc. degrees in physics and applied mathematics at Caltech.
Published
2019-02-27
How to Cite
Pravica, M. G., Schyck, S., Harris, B., Cifligu, P., Kim, E., & Billinghurst, B. (2019). Fluorine chemistry at extreme conditions: Possible synthesis of $HgF_4$. Papers in Physics, 11, 110001. https://doi.org/10.4279/pip.110001
Section
Articles