Intermolecular recognition and crystal packing in molybdenum and tungsten coordination polymers as deduced from powder X-ray diffraction data

The molecular conformations and packing of [(tBuCO2)3M2(mu-X)M2(O2CtBu)3], where M = Mo and W, and X = oxalate and perfluoroterephthalate, determined in the solid-state from powder X-ray diffraction analysis, reveal one-dimensional coordination polymers involving pivalate-oxygen to metal interactions (X = perfluoroterephthalate), and oxalate--as well as pivalate-oxygen to metal bonds (X = oxalate), and allows explanation of the unusual state-dependent chromic properties of these compounds.