Niobium monoxide NbO single crystal growing by floating zone method

Abstract

In this work, a single crystal of niobium monoxide NbO was grown by crucible-free zone melting method. Polycrystalline NbO with ordered cubic structure (sp.gr. Pm-3m) with vacancies in both metal and nonmetal sublattices served as an initial material. According to XRD data, the grown niobium monoxide NbO single crystal has predominant growth in the [111]B1 direction and contains only one ordered cubic phase NbO, its lattice constant is equal to a = 421.2 pm. The growing mechanism of the NbO single crystal was clarified, in accordance with the Kossel and Stransky theory, it was suggested that the single crystal grows layer by layer. Analysis of the Kikuchi lines geometry allowed the orientations and disorientations of single crystal to be determined to high precision. An analysis of the diffraction pattern and intersection of Kikuchi lines showed that the NbO single crystal has (111)B1 facet. The experimental Laue diffraction patterns confirmed this direction of niobium monoxide NbO single crystal growth.