Design and construction of a thermotropic liquid crystal material based on high-nuclear transition-metal cluster-containing polyoxometalates

摘要

Dimethyldioctadecylammonium (DODA(+)) was used as a surfactant to react with the high-nuclear transition-metal cluster-containing polyoxometalate K5Na11[Ni-9(OH)(3)(H2O)(6)(HPO4)(2)(PW9O34)(3)]center dot 52H(2)O (POM-1), resulting in an organic-inorganic hybrid complex (DODA)(16)[Ni-9(OH)(3)(H2O)(6)(HPO4)(2)(PW9O34)(3)]center dot 36H(2)O (SEP-1), which exhibits characteristic thermotropic liquid crystalline behavior. Here, the high-nuclear transition-metal cluster-substituted polyoxoanions were firstly introduced into liquid crystalline materials. The chemical composition of the obtained SEP-1 was determined by IR spectra, elemental analysis, and thermogravimetric (TG) analysis. Also, polarized optical microscopy, differential scanning calorimetry (DSC), and variable temperature X-ray diffraction (VT-XRD) were performed on SEP-1 to confirm its thermotropic liquid crystalline behavior.