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arXiv · 2303.12694

A new room-temperature equation of state of Bi up to 260 GPa

Daniel J. Campbell·Daniel T. Sneed·Earl F. O'Bannon III·Per Söderlind·Zsolt Jenei
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Abstract

At room temperature, bismuth undergoes several structural transitions with increasing pressure before taking on a body-centered cubic (bcc) phase at approximately 8 GPa. The bcc structure is stable to the highest measured pressure and its simplicity, along with its high compressibility and atomic number, make it an enticing choice as a pressure calibrant. We present three data sets on the compression of bismuth in a diamond anvil cell in a neon pressure medium, up to a maximum pressure of about 260 GPa. The use of a soft pressure medium reduces deviatoric stress when compared to previous work. With an expanded pressure range, higher point density, and a decreased uniaxial stress component, we are able to provide more reliable equation of state (EOS) parameters. We also conduct density functional theory (DFT) electronic-structure calculations that confirm the stability of the bcc phase at high pressure.

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Daniel J. Campbell, Daniel T. Sneed, Earl F. O'Bannon III, Per Söderlind, Zsolt Jenei. 2023-03-22. A new room-temperature equation of state of Bi up to 260 GPa. https://doi.org/10.1103/physrevb.107.224104

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