Synthesis, crystal structure and nonlinear optical properties of two novel linear cluster polymers {[MoOS3Cu3(CN)(py)3]•0.5C6H6}n and [WOS3Cu3(CN)(py)4]n

Cluster polymers {[MoOS3Cu3(CN)(py)(3)]. 0.5C(6)H(6)}(n) 1 and [WOS3Cu3(CN)(py)(4)](n) 2 were synthesized by the reaction of (NH4)(2)MO2S2 (M = Mo, W) and CuCN with py. Their structures have been characterized by X-ray diffraction. Both of them show neutral nest-shaped structural units, and every structural unit forms two Cu1-N1-C1-Cu3 bridges with two other structural units leading to infinite one-dimensional polymers. In every unit cell of {[MoOS3Cu3(CN)(py)(3)]. 0.5C(6)H(6)}(n) there are four [MoOS3Cu3(CN)(py)(3)] structural units and two benzene molecules, and the four structural units are from four independent linear polymer molecules which are parallel. In every unit cell of polymer 2, there are four [WOS3Cu3(CN)(py)(4)] structural units too, but they are only from two parallel linear polymer molecules. Polymer 1 shows good nonlinear optical (NLO) absorptive and NLO refractive properties, whereas strong NLO properties of polymer 2 are not observed.