Raman Spectroscopy Study on CsB₃O₅ Crystal−Melt Boundary Layer Structure

Abstract

The structure of the melt near a crystal−melt interface is a fundamental problem in the dynamics of crystal growth. In this work, high-temperature Raman spectroscopy was used to investigate the melt structure near the CsB3O5 (CBO) crystal−melt interface. An ordered boundary layer was observed near the interface; its thickness is larger than 100 µm. An isomerization reaction between 3- and 4-coordinated boron was found in the layer. The ordering of the melt is strongest near the crystal−melt interface and decreases toward the bulk melt. These results have been applied to explain the growth habit of CBO crystal. The predicted growth habit is in good agreement with the observed result.