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.