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The complex superstructure in Mg1-xAlxB2 at x~0.5

H. W. Zandbergen·M. Y. Wu·H. Jiang·M. A. Hayward·M. K. Haas·R. J. Cava
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Abstract

Electron diffraction and high resolution microscopy have been performed on Mg1-xAlxB2 with x~0.5. This composition displays a superstructure with a repeat period of exactly 2c along the c axis and about 10 nm in the a-b plane. The superstructure results in ring-shaped superreflections in the diffraction pattern. Irradiation by a strong electron beam results in a loss of the superstructure and a decrease of about 1% in the c lattice parameter. In-situ heating and cooling on the other hand showed that the superstructure is stable from 100 K to 700 K. Possible origins for the superstructure are proposed.

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H. W. Zandbergen, M. Y. Wu, H. Jiang, M. A. Hayward, M. K. Haas, R. J. Cava. 2001-09-17. The complex superstructure in Mg1-xAlxB2 at x~0.5. https://doi.org/10.1016/s0921-4534(01)01195-9

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