THEORY OF FINITE-FREQUENCY LOCAL FIELD CATASTROPHE WITH APPLICATIONS TO THE SPECTRA OF KCNX-KCL1-X

被引：4

作者：

HOLDEN, AJ ^{[1
]}

HEINE, V ^{[1
]}

INKSON, JC ^{[1
]}

VARMA, CM ^{[1
]}

BOSCH, MA ^{[1
]}

机构：

[1] BELL TEL LABS INC,HOLMDEL,NJ 07733

来源：

JOURNAL OF PHYSICS C-SOLID STATE PHYSICS | 1979年 / 12卷 / 06期

关键词：

D O I：

10.1088/0022-3719/12/6/016

中图分类号：

O469 [凝聚态物理学];

学科分类号：

070205 ;

摘要：

A strong divergence, observed in the relative oscillator strength of the molecular exciton in KCNx-CKl1-x, can involve an increase of two orders of magnitude for a nominal variation in the solution concentration x or temperature T. The theory demonstrates that this enhancement can be accounted for by a finite-frequency local field catastrophe of the form described by Lorentz and used to explain ferroelectricity. A crucial role is played by the background susceptibility at the exciton frequency, due to interband polarisability. It is suggested that the strong temperature dependence is connected with the ordering of the CN- dipoles, which may serve to enhance the interband polarisability. A mean field theory for the phase transitions in pure KCN is also presented.

引用

页码：1035 / 1047

页数：13

共 16 条

[1] QUANTUM THEORY OF DIELECTRIC CONSTANT IN REAL SOLIDS [J].