The complex superstructure in Mg1-xAlxB2 at x approximate to 0.5
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 diffrac...
Main Authors: | , , , , , |
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Format: | Journal article |
Language: | English |
Published: |
2002
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Summary: | 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 to 700 K. Possible origins for the superstructure are proposed. © 2002 Published by Elsevier Science B.V. |
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