Acoustic and optical phonons and their dispersion in model ferroelastics Hg2Cl2

被引：1

作者：

Kvasov, A. A. ^{[1
]}

Markov, Yu. F. ^{[2
]}

Roginskii, E. M. ^{[2
]}

Smirnov, M. B. ^{[1
]}

机构：

[1] St Petersburg State Univ, St Petersburg 199034, Russia

[2] Russian Acad Sci, AF Ioffe Phys Tech Inst, St Petersburg 194021, Russia

来源：

PHYSICS OF THE SOLID STATE | 2009年 / 51卷 / 07期

关键词：

CRYSTALS;

D O I：

10.1134/S1063783409070245

中图分类号：

O469 [凝聚态物理学];

学科分类号：

070205 ;

摘要：

Thefrequency dispersion curve of acoustic and optical phonons are calculated and constructed, and the density of states of the phonon spectrum is obtained for Hg2Cl2 crystals. The influence of the hydrostatic pressure on the frequencies of acoustic and optical phonons and their dispersion is analyzed theoretically. It is revealed that an increase in the pressure leads to a considerable softening of the slowest acoustic TA branch (soft mode) at the X point of the Brillouin zone boundary. This behavior is consistent with the phenomenological Landau theory and correlate with experiments.

引用

页码：1426 / 1430

页数：5