Effects of magnetic nanoparticles with different surface coating on the phase transitions of octylcyanobiphenyl liquid crystal

被引：44

作者：

Cordoyiannis, George ^{[1
]}

Kurihara, Lynn K. ^{[2
]}

Martinez-Miranda, Luz J. ^{[3
]}

Glorieux, Christ ^{[1
]}

Thoen, Jan ^{[1
]}

机构：

[1] Katholieke Univ Leuven, Dept Natuurkunde Sterrenkunde, Lab Akoestiek Therm Fys, B-3001 Louvain, Belgium

[2] USN, Res Lab, Washington, DC 20375 USA

[3] Univ Maryland, Dept Mat Sci & Engn, College Pk, MD USA

来源：

PHYSICAL REVIEW E | 2009年 / 79卷 / 01期

关键词：

coatings; critical exponents; liquid crystal phase transformations; magnetic particles; nanoparticles; nematic liquid crystals; organic compounds; smectic liquid crystals; HEAT-CAPACITY; X-RAY; BEHAVIOR; SCATTERING; PARTICLES;

D O I：

10.1103/PhysRevE.79.011702

中图分类号：

O35 [流体力学]; O53 [等离子体物理学];

学科分类号：

070204 ; 080103 ; 080704 ;

摘要：

The impact of magnetic nanoparticles with different surface coating upon the isotropic-to-nematic and nematic-to-smectic-A phase transitions of the liquid crystal octylcyanobiphenyl is explored by means of high-resolution adiabatic scanning calorimetry. A shrinkage of the nematic range is observed, which is strongly dependent on the surface coating of the nanoparticles. The isotropic-to-nematic transition remains weakly first order while the nematic-to-smectic-A is continuous with the effective critical exponent alpha values (0.35 and 0.39, depending on the coating) between the pure octylcyanobiphenyl value of 0.31 +/- 0.03 and the theoretical tricritical value of 0.5.

引用

页数：5

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