Symmetry breaking at the phase transitions in ferroelectric pyridinium salts

被引：7

作者：

Czarnecki, P ^{[1
]}

机构：

[1] Adam Mickiewicz Univ Poznan, Inst Phys, PL-61614 Poznan, Poland

来源：

PHASE TRANSITIONS | 2003年 / 76卷 / 9-10期

关键词：

phase transitions; ferroelectrics; molecular crystals; TETRAFLUOROBORATE; REORIENTATION; PERCHLORATE;

D O I：

10.1080/014115903100001613617

中图分类号：

O7 [晶体学];

学科分类号：

0702 ; 070205 ; 0703 ; 080501 ;

摘要：

The phase transitions in ferroelectric pyridinium tetrafluoroborate (PyBF4) and pyridinium Perchlorate (PYClO4) have been characterized by structural studies. The continuous ferroelectric phase transition at 238.7 K in PyBF4 appears to be a unique case for multiaxial ferroelectrics, while the first order phase transition in PyClO4 at 248 K is consistent with the Landau theorem for deducing the character of phase transitions from symmetry considerations. The phase transition in both materials is caused by ordering of the pyridinium cation as well as tetrahedral anions.

引用

页码：801 / 805

页数：5

共 13 条

[1]

BLINC R, 1974, SOFT MODES FERROELEC, P98

[2] SECOND-ORDER PHASE TRANSITIONS CHARACTERIZED BY A DEFORMATION OF UNIT CELL [J].