Uniformly dispersed copper oxide nanoparticles in poly(vinyl alcohol) (CuO-PVA) have been synthesized by the sonochemical method. The properties of the as-prepared composite material are characterized by XRD, DSC, thermogravimetric analysis (TGA), TEM, and diffuse reflection spectroscopy (DRS). A band gap of 2.1 eV is estimated from DRS measurements. The controlled crystal growth of copper oxide has been studied by using the as-prepared CuO-PVA composite as seed for the crystal growth of copper oxide. Well-shaped crystals of 1 µm in length were grown.

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UV photolysis of a cyclohexane solution of W(CO) 6 in the presence of 2,5-dihydrofuran (DHF) yields W(CO) 5 (η 1 (O)-DHF) with a bimolecular rate constant on the order of 10 7 L mol -1 s -1 . Time-resolved IR (TRIR) absorption spectroscopy is used to monitor the consequent intramolecular isomerization to W(CO) 5 (η 2 -(C,C)-DHF), which occurs with a rate constant on the order of 1-10 s -1 at 20-60 °C; activation parameters for the isomerization are determined to be ∆H q ) 17.3 ( 0.3 kcal/mol and ∆S q ) 0.9 ( 0.9 eu.