Structural Stability of γ-Boron under High Pressure up to 126 GPa with Fine Pressure Increments
Author:
Zhong Cheng1,
Mai Di1,
Li Xiangdong1,
Wang Junke1,
Dai Rucheng1,
Wang Zhongping1,
Sun Xiaoyu1,
Zhang Zengming1ORCID
Affiliation:
1. Deep Space Exploration Laboratory, School of Physical Sciences, University of Science and Technology of China, Hefei 230026, China
Abstract
The structural stability of γ-boron is investigated using Raman spectra and DFT calculations under high pressures, up to 126 GPa, at ambient temperature. The pressure dependence of all the Raman-active modes of the γ-boron is reported. We also observe amusing changes within the B3g and B1g Raman-active vibrational modes, which result in the phenomenon of first merging and then separating the Raman peaks. In addition to the Raman measurements, the changes in crystal structure and force constants are calculated to reasonably explain the discrepancy between the two Raman modes in response to pressure. The results of the continuous shifts for all Raman modes and the unit-cell parameters, as well as volume with increasing pressure, indicate that there is no structural transformation of γ-boron below this pressure value, with no changes in either symmetry or structure.
Funder
Frontier Scientific Research Program of Deep Space Exploration Laboratory
National Natural Science Foundation of China
National Key Laboratory of Shock Wave and Detonation Physics
Subject
Physics and Astronomy (miscellaneous),General Mathematics,Chemistry (miscellaneous),Computer Science (miscellaneous)
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