利用核磁共振氢谱的哈勒分析获得分子序列取向参数

doi:10.11938/cjmr20182685

摘要/Abstract

摘要： 本文通过全氢液晶材料的核磁共振氢谱（¹H NMR）的哈勒关联研究推测了分子序列取向参数，包括随温度变化的双峰距离及全谱图的半高峰宽.通过哈勒拟合并外推所得到的4'-正戊基-4'-氰基联苯（5CB）和混合液晶E7分子取向参数，与其它方法获得的取值一致.

关键词: 丝状液晶, 取向参数, 哈勒分析, 核磁共振氢谱(¹H NMR)

Abstract: The Haller relationship was applied to estimate the nematic order parameter S from ¹H NMR spectra of fully protonated liquid crystals aligned in the magnetic field. The NMR line shapes were approximated as doublets of very broad peaks. Both the temperature-dependent doublet Splitting and the full width at half maximum of the whole spectra were used for Haller extrapolation. The order parameters obtained with the proposed approach for 4-cyano-4'-pentylbiphenyl (5CB) and the nematic mixture E7 were found to be in good agreement with previously reports.

Key words: nematic liquid crystal, order parameter, Haller analysis, ¹H NMR

中图分类号:

O482.53

唐明学, SCHMIDT Claudia. 利用核磁共振氢谱的哈勒分析获得分子序列取向参数[J]. 波谱学杂志, 2019, 36(2): 138-147.

TANG Ming-xue, SCHMIDT Claudia. Estimation of Nematic Order Parameters via Haller Analysis of ¹H NMR Spectra of Liquid Crystals[J]. Chinese Journal of Magnetic Resonance, 2019, 36(2): 138-147.

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