Synthesis of diamondoid lanthanide-polyoxometalate solids as tunable photoluminescent materials

The reaction between polyoxometalate (POM) [TBA](12)[WZn{Zn(H(2)O)}(2)(ZnW(9)O(34))(2)] (TBA = tetrabutyl ammonium) and lanthanide (Ln) nitrate (Ln = La, Eu and Tb) in a mixed solvent of CH(3)CN and DMF yielded three noncentrosymmetric diamondoid Ln-POM solid materials, {[Ln(2)(DMF)(8)(H(2)O)(6)][ZnW(12)O(40)]}·4DMF (Ln-POM; Ln = La, Eu and Tb). In these compounds, the {ZnW(12)O(40)} unit, transferred from the metastable [WZn{Zn(H(2)O)}(2)(ZnW(9)O(34))(2)] cluster, acts as a tetradentate ligand to connect with four Ln nodes, while the Ln ion links up two {ZnW(12)O(40)} units. These compounds generated interesting luminescence emissions that are dependent on the Ln ions and their ratios. White light emission was obtained by a doped approach with a rational ratio of the Eu(3+) and Tb(3+) ions.