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    Growth of LiCoO2 Single Crystals by the TSFZ Method
    (Washington, DC : ACS Publ., 2018) Nakamura, Shigenobu; Maljuk, Andrey; Maruyama, Yuki; Nagao, Masanori; Watauchi, Satoshi; Hayashi, Takeshi; Anzai, Yutaka; Furukawa, Yasunori; Ling, Chris D.; Deng, Guochu; Avdeev, Maxim; Büchner, Bernd; Tanaka, Isao
    We have grown LiCoO2 single crystals by the traveling solvent floating zone (TSFZ) growth with Li-rich solvent, having observed the incongruent melting behavior of LiCoO2 between 1100 and 1300 °C. The optimum growth conditions in terms of atmosphere and solvent composition were determined to be Ar flow and an atomic ratio Li/Co 85:15, respectively. The crystals grown using a conventional-mirror-type furnace contained periodic inclusions of a Co-O phase due to the influence of Co-O phase segregation on the stability of the molten zone during growth. By using a tilted-mirror FZ furnace, inclusion-free LiCoO2 crystals of about 5 mm in diameter and 70 mm long were obtained at a tilting angle Î = 10°. The grown crystals were confirmed to be single-domain by neutron Laue diffraction. © 2018 American Chemical Society.
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    Crystal growth and thermodynamic investigation of Bi2M2+O4 (M = Pd, Cu)
    (London : RSC, 2021) Wolff, Nora; Klimm, Detlef; Habicht, Klaus; Fritsch, Katharina
    Phase equilibria that are relevant for the growth of Bi2MO4 have been studied experimentally, and the ternary phase diagrams of Bi2O3–PdO2–Pd and Bi2O3–Cu2O–CuO and its isopleth section Bi2O3–CuO were redetermined. It is shown that every melting and crystallization process is always accompanied by a redox process at the phase boundary and that for both title compounds, the valence of the transition metal is lowered during melting. Vice versa, during crystal growth, O2 must be transported through the melt to the phase boundary. Based on these new insights provided by our thermodynamic studies, Bi2CuO4 single crystals with a length of up to 7 cm and a diameter of 6 mm were grown by the OFZ technique to be used for investigations of magnetic, electronic and thermal transport properties. The grown crystals were characterized by powder X-ray diffraction, Laue, magnetization and specific heat measurements.