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Abstract: Single crystals of the spin dimer compound Pb2V3O9 were grown for the first time by the floating zone method. Room temperature single-crystal X-ray diffraction measurements confirm their crystallinity and structure. The crystal growth process is discussed in detail and high temperature differential scanning calorimetry measurements that show a structural phase transition from a monoclinic to a triclinic unit cell at 759(1)K are presented. [Copyright &y& Elsevier]

High quality epitaxial MgxZn1−xO films are essential for the fabrication of ZnO/MgxZn1−xO heterostructures. In this work, MgxZn1−xO (0⩽x⩽0.33) thin films are epitaxially grown on (0 1 1¯ 2) r-sapphire substrates by metalorganic chemical vapor deposition. A thin ZnO buffer layer in the order of 50 A˚ is found to be critical for the growth of single crystal MgxZn1−xO (0⩽x⩽0.33) films with a wurtzite-type structure. The energy bandgap of MgxZn1−xO films as a function of Mg composition was deduced using a UV-Visible spectrophotometer at room temperature in conjunction with Rutherford backscattering spectroscopy measurements. The epitaxial relationship between the wurtzite-type MgxZn1−xO films and r-sapphire substrates is determined to be (1 1 2¯ 0) MgxZn1−xO∥(0 1 1¯ 2) Al2O3, and [0 0 0 1] MgxZn1−xO∥[0 1¯ 1 1] Al2O3. In-plane X-ray diffraction reflections show the lower lattice mismatch along the c-axis of the MgxZn1−xO films on r-sapphire substrates. High resolution transmission electron microscopy analysis of the film/substrate interface indicates the region in the film near the interface is crystalline though strained. [Copyright &y& Elsevier]