Synthesis, characterization, and tuning of the liquid crystal properties of ionic materials based on the cyclic polyoxothiometalate [{Mo4O4S4(H2O)3(OH)2}2(P8W48O184)]36-

A series of compounds resulting from the ionic association of a nanoscopic inorganic cluster of formula [K2NaxLiy{Mo4O4S4(OH)(2)(H2O)(3)}(2)(HzP8W48O184)]((34-x-y-z)-), 1, with several organic cations such as dimethyldioctadecylammonium DODA(+), trimethylhexadecylammonium TMAC(16+), alkylmethylimidazoliums mimC(n)(+) (n = 12-20) and alkyl-dimethylimidazoliums dmimC(n)(+) (n = 12 and 16) was prepared and characterized in the solid state by FT-IR, EDX, Elemental analysis, TGA and solid state NMR. The solid state NMR experiments performed on H-1, C-13 and P-31 nuclei evidenced the interactions between the cations and as well as the organization of the alkyl chains of the cations within the solid. Polarized optical microscopy, DSC and SA-XRD experiments implicated mesomorphic phases for DODA(+) and mimC(n)(+) salts of . The crystallographic parameters were determined and demonstrated that the inter-lamellar spacing could be controlled upon changing the length of the alkyl chain, a very interesting result if we consider the huge size of the inorganic cluster and the simple nature of the cations.