Ionic liquid crystals: Hexafluorophosphate salts

Charles M. Gordon*, John D. Holbrey, Alan R. Kennedy, Kenneth R. Seddon

*Corresponding author for this work

Research output: Contribution to journalArticle

618 Citations (Scopus)

Abstract

A series of novel hexafluorophosphate salts, based on N,N′-dialkylimidazolium and substituted N-alkylpyridinium cations, display liquid crystalline behaviour at temperatures above their melting point. The temperature range over which liquid crystalline behaviour is observed increases markedly with increasing alkyl chain length. Alkyl substitution at the 3- and 4-positions on the pyridinium ring results in a decrease in the melting point compared with the equivalent unsubstituted salt, but also leads to a large decrease in the tendency towards liquid crystalline behaviour (or mesogenicity). The salts prepared are fully characterised using a wide variety of techniques, including NMR and IR spectroscopy, DSC, and single crystal X-ray diffraction in the case of 1-dodecyl-3-methylimidazolium hexafluorophosphate. The effect of preparing mixtures containing different proportions of two cations is also reported.

Original languageEnglish
Pages (from-to)2627-2636
Number of pages10
JournalJournal of Materials Chemistry
Volume8
Issue number12
DOIs
Publication statusPublished - 01 Jan 1998

    Fingerprint

Cite this