Gulec Ahmet, Yu Xiaoxiang, Taylor Matthew, Perepezko John H, Marks Laurence
Department of Materials Science and Engineering, Northwestern University, 2220 Campus Drive, Evanston, Illinois 60208, USA.
Department of Materials Science and Engineering, University of Wisconsin-Madison, 1509 University Avenue, Madison, Wisconsin 53706, USA.
Acta Crystallogr A Found Adv. 2016 Nov 1;72(Pt 6):660-666. doi: 10.1107/S2053273316012286. Epub 2016 Oct 3.
Z-contrast imaging, electron diffraction, atom-probe tomography (APT) and density functional theory calculations were used to study the crystal structure of the MoSi phase which was previously reported to have an A15 crystal structure. The results showed that MoSi has an incommensurate crystal structure with a non-cubic unit cell. The small off-stoichiometry in composition of the sample which was revealed by APT and atomic resolution Z-contrast imaging suggested that site substitution caused the development of split atomic positions, disorder and vacancies.
利用Z衬度成像、电子衍射、原子探针断层扫描(APT)和密度泛函理论计算来研究先前报道具有A15晶体结构的MoSi相的晶体结构。结果表明,MoSi具有非等轴晶系晶体结构,其晶胞为非立方晶胞。APT和原子分辨率Z衬度成像揭示的样品成分中较小的非化学计量比表明,位点取代导致了分裂原子位置、无序和空位的形成。