%0 Journal Article
%A Cheng, Hu
%A Zhang, Junran
%A Lin, Chuanlong
%A Li, Xiaodong
%A Peng, Feng
%A Li, Gong
%A Li, Yanchun
%D 2018
%T Persistence of the R3m Phase in
Powder GeTe at High Pressure and High Temperature
%U 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
%R 10.1021/acs.jpcc.8b06511.s001
%2 https://acs.figshare.com/ndownloader/files/13769789
%K B 1
%K phase-change material
%K High Temperature
%K Powder GeTe
%K R 3 m phase
%K heating X-ray powder diffraction experiment
%K PCM
%K High Pressure
%K R 3 m Phase
%K synchrotron X-ray diffraction
%K displacive transitions
%K Peierls distortion
%K lattice parameters
%K 15.8 GPa
%K B 1 phase
%K rock-salt phase
%K R 3 m
%K compression ratio
%K ambient pressure
%K space group R 3 m
%X As a phase-change
material (PCM), rhombohedral GeTe (space group R3m) 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 R3m 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 R3m to B1 is caused by changes to the compression ratio of
lattice parameters in the R3m phase
under high pressure/temperature. These findings provide insight into
transitions of PCMs, relevant to other materials undergoing displacive
transitions under high pressure/temperature.
%I ACS Publications