A series of dilute liquid crystalline solvents are used to study the effect of slight anisotropy caused by partial alignment on chemical shift and residual dipolar coupling (RDC) in small molecules. The residual dipolar couplings between protons in solutes are found to be almost independent of the local environment. It is also found that the chemical shift does not change over the concentration range observed. A linear relationship between residual dipolar coupling and liquid crystal concentration is observed at relatively low concentrations, but is severely violated at high concentrations.

We report in this article the application of a series of weakly ordered liquid crystal solvents for liquid state nuclear magnetic resonance (NMR) spectroscopy. The solvents are a n‐alkyl‐poly(ethylene glycol)/n‐alkyl alcohol non‐ionic liquid crystal system, first proposed by Ruckert and Otting (J. Am. Chem. Soc. 2000, 122, 7793). The merits of these solvents are further demonstrated by using them with a homogeneous polymer PEO which is one of the most studied polymer electrolyte materials, thus offering an answer to the question of whether the weak anisotropy introduced by liquid crystal solvents has any connection with the large‐scale (≥ one nanometer) heterogeneity (tertiary or higher orders of structure) of the system under study.

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