Crystallographic and spectroscopic analysis of 9,10-bis-alkyl imidazolium anthracene hexatungstate supramolecular complexes

Abstract

This article describes the ionic and supramolecular association of bis-dialkyl imidazolium anthracene dications with hexametalate cluster anions. In the relevant compounds, the length of the alkyl chain was varied to observe its effect on the crystal packing. Despite the endothermicity in the crystals due to structural incompatibility between planar anthracene and spherical polyoxometalate ion, packing stability is attained by coulombic interaction together with the supramolecular interactions between the components. The nature of supramolecular interactions depends on the number of carbon atoms in the alkyl chain in the organic counterparts of the crystals which ultimately modifies the packing pattern. Variation of supramolecular interactions with alteration of alkyl chain length leads to diversity in crystal packing patterns in 9,10-bis-alkylimidazolyl anthracene and hexametalate cluster-based compounds.