Investigation of vibration spectrum ferroelectric semiconductor SbSBr nanowire

Abstract The temperature dependence of vibration spectra of one SbSBr chain (nanowire) in the direction of the c ( z )-axis has been calculated in quasiharmonic approximation by diagonalization of dynamical matrix. The vibrational frequencies in the direction of c ( z )-axis have been derived by fitting of the experimental low-frequency ω s 2 of soft infrared ( IR ) mode of bulk-size SbSBr with the theoretical quasiharmonic low-frequency ω 2 of SbSBr nanowires. In this work the nature of anharmonism and temperature dependence of force constants between atoms in SbSBr crystal along c ( z )-axis have been discussed. The anharmonism of all soft (at BZ k =0) modes has been created by the interaction between phonons.