Layered α-In2Se3has been studied using a concomitant 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, that 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 F-f formalism, the β'-In2Se3 structure remains stable up to 45 GPa, without a clear indication of a phase transition towards 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.
@article{arxiv.2502.05927,
title = {High pressure structural and lattice dynamics study of {\alpha}-In$_2$Se$_3$},
author = {Shiyu Feng and Baihong Sun and Wenting Lu and Haikai Zou and Chenxin Wei and Qian Zhang and Bihan Wang and Martin Kunz and Hirokazu Kadobayashi and Azkar Saeed Ahmad and Elad Koren and Elissaios Stavrou},
journal= {arXiv preprint arXiv:2502.05927},
year = {2025}
}