Structural Evolution of β’-In₂Se₃ under Pressure

Abstract

The structural evolution from β’ phase to β phase of the In2Se3 under high pressure is studied by X-ray diffraction (XRD) and Raman scattering. The XRD spectra show that the crystal transforms from β’ phase to β phase at 11.5 GPa, which is consistent with the previous studies. However, the red shift of Ag 4 Raman mode shifts at pressure ranging from 8.8 GPa up to 15.2 GPa which associates with the stretching In-Se bonds under high pressure. The result indicates that the change from low-symmetric phase to high-symmetric phase of the layered In2Se3.

Emission Dipole and Pressure‐Driven Tunability of Second Harmonic Generation in vdWs Ferroelectric NbOI2

“…P1 exhibits an abnormal redshift with the increase of pressure, which can be attributed to the interlayer slip [ 50 ] and the softening of phonons. [ 51 ] Meanwhile, the Raman intensity of P7 is enhanced with the increasing pressure, indicating the enhancement of distortion in the [NbO 2 I 4 ] octahedral. Moreover, we investigated the polarization dependence SHG spectra in the increasing‐pressure process (Figure S9, Supporting Information and inset images in Figure 4b).…”