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Synchrotron X-ray study of polycrystalline wurtzite Zn1-xMgxO (0 <= x <= 0.15): Evolution of crystal structure and polarization

Young-Il Kim·Katharine Page·Ram Seshadri
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Abstract

The effect of Mg-substitution on the crystal structure of wurtzite ZnO is presented based on synchrotron X-ray diffraction studies of polycrystalline Zn1-xMgxO (0 <= x <= 0.15). Increase in Mg concentration results in pronounced c-axis compression of the hexagonal lattice, and in diminution of the off-center cation displacement within each tetrahedral ZnO4 unit. Going from ZnO to Zn0.85Mg0.15O, significant changes in the ionic polarization are observed (-5.6 to -4.8 uC/cm2), despite only subtle increments in the cell volume (~0.03 %) and the ab-area dimension (~0.1 %). The optical properties of the samples have also been characterized and the band gap changes from 3.24 eV (ZnO) to 3.35 eV (Zn0.85Mg0.15O).

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Young-Il Kim, Katharine Page, Ram Seshadri. 2006-11-15. Synchrotron X-ray study of polycrystalline wurtzite Zn1-xMgxO (0 <= x <= 0.15): Evolution of crystal structure and polarization. https://doi.org/10.1063/1.2711289

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