Is Curie-Weiss law valid in every ferro-to-para transition?

被引：13

作者：

Kaur, S

Thakur, AK

Choudhary, A

Bawa, SS

Biradar, AM

Annapoorni, S

机构：

[1] Natl Phys Lab, New Delhi 110012, India

[2] Univ Delhi, Dept Phys & Astrophys, Delhi 110007, India

来源：

APPLIED PHYSICS LETTERS | 2005年 / 87卷 / 10期

关键词：

D O I：

10.1063/1.2042539

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

The Curie-Weiss law is obeyed where there is a change in the order parameter and the symmetry of molecules at the transition temperature (T-c) of ferro-to-para phase. The ferroelectric transition is not strictly governed by the Curie-Weiss law. In fact, a number of solid ferroelectrics show deviation from the Curie-Weiss law. It has been shown in the present letter that the de-Vries electroclinic liquid crystals, with a wide smectic A (Sm-A) phase and a high electroclinic effect, do not obey the Curie-Weiss law. The nonlayer shrinkage leads to symmetry conservation that makes the observance of soft mode impossible and hence the deviation. (c) 2005 American Institute of Physics.

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页数：3

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