10.1021/acs.jpcc.8b06511.s001
Hu Cheng
Hu
Cheng
Junran Zhang
Junran
Zhang
Chuanlong Lin
Chuanlong
Lin
Xiaodong Li
Xiaodong
Li
Feng Peng
Feng
Peng
Gong Li
Gong
Li
Yanchun Li
Yanchun
Li
Persistence of the <i>R</i>3<i>m</i> Phase in
Powder GeTe at High Pressure and High Temperature
American Chemical Society
2018
B 1
phase-change material
High Temperature
Powder GeTe
R 3 m phase
heating X-ray powder diffraction experiment
PCM
High Pressure
R 3 m Phase
synchrotron X-ray diffraction
displacive transitions
Peierls distortion
lattice parameters
15.8 GPa
B 1 phase
rock-salt phase
R 3 m
compression ratio
ambient pressure
space group R 3 m
2018-11-28 00:00:00
Journal contribution
https://acs.figshare.com/articles/journal_contribution/Persistence_of_the_i_R_i_3_i_m_i_Phase_in_Powder_GeTe_at_High_Pressure_and_High_Temperature/7438781
As a phase-change
material (PCM), rhombohedral GeTe (space group <i>R</i>3<i>m</i>) was believed to transform to the cubic
rock-salt phase (B1) at 3–4 GPa, associated with the disappearance
of a Peierls distortion. However, using a combination of synchrotron
X-ray diffraction and theoretical calculations, we found that the <i>R</i>3<i>m</i> phase persists from ambient pressure
up to pressures of about 15.8 GPa, in contrast to previous reports.
Neither was the B1 phase observed in a heating X-ray powder diffraction
experiment. The spurious transformation from <i>R</i>3<i>m</i> to B1 is caused by changes to the compression ratio of
lattice parameters in the <i>R</i>3<i>m</i> phase
under high pressure/temperature. These findings provide insight into
transitions of PCMs, relevant to other materials undergoing displacive
transitions under high pressure/temperature.