In situ study on the structural transition in YBO 3 through Raman spectroscopy

Abstract

Raman spectroscopy is a powerful tool to judge the fundamental building units contained in crystal structure. In this work, it was used to investigate the basic structural groups involved in the low temperature (LT) and high temperature (HT) phase YBO 3. The characteristic Raman vibrational bands of the LT and HT phases YBO 3 were identified respectively. The characteristic vibrational peaks of the LT phase YBO 3 locate around 410 cm −1 and 500 cm −1, both of them are attributed to the ring bending modes of B 3O 9 group. The strong characteristic vibrational band of the HT phase YBO 3, arising from the symmetric stretching mode of BO 3 group, locates around 940 cm −1. A structural phase transition with a large thermal hysteresis was found. During the phase transition process, the B–O bonds of the BO 4 groups break and the B 3O 9 rings cleave into the BO 3 plane conjugated groups.