Ion binding of the organic counterion methyl phosphonate in amphiphilic micellar nematic liquid crystals

Abstract

The ₁H N.M.R. of the methyl phosphonate ion has been used as a probe in the investigation of the reversal of the diamagnetic anisotropy in amphiphilic nematic liquid crystals. Three classes of aromatic counterion substitution have been investigated involving sodium and ceasium decylsulphate and the aromatic counterions trimethylanalinium and analinium. It was found that, in the absence of diamagnetic anisotropy considerations, in the trimethylanalinium/ceasium decylsulphate system the signs of the ₁H N.M.R. dipolar couplings of the methyl phosphonate ion were reversed. This is explained in terms of ion binding and various degrees of protonation of the methyl phosphonate species.