Liquid crystalline and dielectric properties of homologous series of substituted 1,3,4-oxadiazoles

被引：24
作者：
Hetzheim, A
Wasner, C
Werner, J
Kresse, H
Tschierske, C
机构：
[1] Univ Greifswald, Inst Chem & Biochem, D-17487 Greifswald, Germany
[2] Univ Halle Wittenberg, Inst Phys Chem, D-06108 Halle, Germany
[3] Univ Halle Wittenberg, Inst Organ Chem, D-06120 Halle, Germany
来源：
LIQUID CRYSTALS | 1999年 / 26卷 / 06期
关键词：
D O I：
10.1080/026782999204570
中图分类号：
O6 [化学];
学科分类号：
0703 ;
摘要：
Three homologous series of 2-alkylthio-5-phenyl-1,3,4-oxadiazole derivatives were synthesized [1, 2] and their liquid crystalline and dielectric properties investigated. Depending on the chain length, nematic, smectic A and smectic C phases were observed [1]. Dielectric investigations indicate a cross over of epsilon(parallel to o) and epsilon(perpendicular to o) at the N/SmA phase transition. This is explained by a transition from a more statistical into an antiparallel correlation of the dipoles, mainly caused by steric effects.
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页码：885 / 891
页数：7
相关论文
共 24 条
[11]  
HETZHEIM A, 1998, IN PRESS J HETEROCYC
[12]  
HILL NE, 1969, DIELECTRIC PROPERTIE, P52
[13]   LIQUID-CRYSTALLINE SWALLOW-TAILED COMPOUNDS .2. DIELECTRIC-RELAXATION [J].
KRESSE, H ;
RABENSTEIN, P ;
STETTIN, H ;
DIELE, S ;
DEMUS, D ;
WEISSFLOG, W .
CRYSTAL RESEARCH AND TECHNOLOGY, 1988, 23 (01) :135-140
[14]  
KRESSE H, 1987, PHYS STATUS SOLIDI A, V100, P83
[15]  
KRESSE H, 1978, Z PHYS CHEM, V259, P4
[16]   EINE EINFACHE THEORIE DER DIELEKTRISCHEN EIGENSCHAFTEN HOMOGEN ORIENTIERTER KRISTALLINFLUSSIGER PHASEN DES NEMATISCHEN TYPS [J].
MAIER, W ;
MEIER, G .
ZEITSCHRIFT FUR NATURFORSCHUNG PART A-ASTROPHYSIK PHYSIK UND PHYSIKALISCHE CHEMIE, 1961, 16 (03) :262-267
[17]  
MARTIN AJ, 1971, S FARADAY SOC, V5, P1919
[18]   2,5-DISUBSTITUTED 1,3,4-OXADIAZOLES - SYNTHESIS AND MESOMORPHIC BEHAVIOR [J].
PARRA, M ;
BELMAR, J ;
ZUNZA, H ;
ZUNIGA, C ;
FUENTES, G ;
MARTINEZ, R .
JOURNAL FUR PRAKTISCHE CHEMIE-CHEMIKER-ZEITUNG, 1995, 337 (03) :239-241
[19]   SYNTHESES WITH ALKENEDIAZONIUM SALTS .5. SYNTHESIS AND STRUCTURE OF 1,3,4-OXADIAZOLES, 6H-1,3,4-OXADIAZINES, AND 5,6-DIHYDRO-4H-1,3,4-OXADIAZINES [J].
SAALFRANK, RW ;
WEISS, B ;
PETERS, K ;
VONSCHNERING, HG .
CHEMISCHE BERICHTE-RECUEIL, 1985, 118 (10) :4026-4034
[20]   Biaxial smectic phases in non-linear mesogens: optical properties and phase behaviour of an oxadiazole liquid crystal [J].
Semmler, KJK ;
Dingemans, TJ ;
Samulski, ET .
LIQUID CRYSTALS, 1998, 24 (06) :799-803
123