DEUTERIUM SPIN-LATTICE RELAXATION IN THERMOTROPIC LIQUID-CRYSTALS - STUDY OF 4,4'-DI-NORMAL-HEPTYLAZOBENZENE, 4,4'-DI-NORMAL-HEPTYLAZOXYBENZENE AND 4,4'-DI-NORMAL-OCTYLAZOXYBENZENE

被引：4

作者：

CATALANO, D ^{[1
]}

GEPPI, M ^{[1
]}

VERACINI, CA ^{[1
]}

FORTE, C ^{[1
]}

机构：

[1] CNR,IST CHIM QUANTIST & ENERGET MOLEC,I-56100 PISA,ITALY

来源：

MOLECULAR CRYSTALS AND LIQUID CRYSTALS | 1992年 / 221卷

关键词：

D O I：

10.1080/10587259208037515

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

The deuterium Zeeman spin-lattice relaxation times T1Z in 4,4'-di-n-heptylazobenzene (HB), 4,4'-di-n-heptylazoxybenzene (HAB), and 4,4'-di n-octylazoxybenzene (OAB) deuterated on the aromatic rings and on the first methylene group of the chains were measured at 10 and 46.04 MHz by means of the inversion-recovery technique. Measurements were made throughout the mesomorphic range and also in the isotropic phase. The relaxation rates show a discontinuity at the isotropic-nematic transition for all deuterons not ascribable to the onset of orientational order. The trends of lnR are linear within the different phases except near phase transitions, and allow to obtain apparent activation energies for the overall motions of the different C-D bonds.

引用

页码：7 / 17

页数：11

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