Raman and infrared study of phase transitions in solid HBr under pressure

作     者：E. Katoh H. Yamawaki H. Fujihisa M. Sakashita K. Aoki 

作者机构：Core Research for Evolutional Science and Technology Japan Science and Technology Corporation Kawaguchi Saitama 332-0012 Japan 

出 版 物：《Physical Review B》 (物理学评论B辑：凝聚态物质与材料物理学)

年 卷 期：1999年第59卷第17期

页      面：11244-11244页

核心收录：

学科分类：07[理学] 0702[理学-物理学] 

摘      要：Phase transition in solid HBr has been investigated by Raman and infrared spectroscopy up to 50 GPa at 298 K. The liquid transforms to a cubic structure (Fm3m) with a bromine fcc lattice at 0.5 GPa and further to an orthorhombic structure (Cmc21) consisting of zigzag chains of hydrogen-bonded molecules at 13±0.5GPa. At about 39±2GPa, Raman peaks related to the molecular stretch and rotation disappear and two lattice peaks remain. The Cmc21 orthorhombic structure transforms into a Cmcm orthorhombic structure with symmetrized hydrogen bonds. The symmetrized phase is instable; HBr molecules begin to dissociate after the bond symmetrization and Br2 molecules are formed.