Feng Shiyu, Sun Baihong, Lu Wenting, Zou Haikai, Wei Chenxin, Zhang Qian, Wang Bihan, Kunz Martin, Kadobayashi Hirokazu, Ahmad Azkar Saeed, Koren Elad, Stavrou Elissaios
Department of Materials Science and Engineering, Guangdong Technion-Israel Institute of Technology, Shantou 515063, China.
Department of Materials Science and Engineering, Technion-Israel Institute of Technology, Haifa 3200003, Israel.
J Chem Phys. 2025 Jun 21;162(23). doi: 10.1063/5.0266372.
Layered α-In2Se3 has been studied using a combined in situ synchrotron angle-dispersive powder x-ray diffraction and Raman spectroscopy study in a diamond anvil cell up to 60+ GPa, at room temperature. Helium, which remains fairly hydrostatic up to the highest pressure in this study, was used as the pressure-transmitting medium. The results from both experimental methods reveal a pressure-induced structural phase transition from α-In2Se3 to a monoclinic β'-In2Se3 structure at ≈1 GPa, in agreement with previous studies. Based on our detailed measurements using both experimental techniques and the F-f formalism, the β'-In2Se3 structure remains stable up to 45 GPa, without a clear indication of a phase transition toward the previously reported β-In2Se3 phase. Above this pressure, In2Se3 adopts a disordered solid-solution-like orthorhombic structure, phase IV. The results are discussed in comparison with the relevant previous studies of α-In2Se3 under pressure.
