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Updated: Jun 8, 2026
Molten-Salt Synthesis of Complex Metal Oxide Nanoparticles
Published on: October 27, 2018
Linear Tetramer Formation in Nonmagnetic Pyrochlore Niobate
Shota Nishida1, Shunsuke Kitou1, Shingo Toyoda2
1The University of Tokyo, Department of Advanced Materials Science, Kashiwa 277-8561, Japan.
None:
We investigate displacive short-range order in pyrochlore Y_{2}Nb_{2}O_{7}, which exhibits a nonmagnetic insulating state despite the presence of formally tetravalent Nb^{4+} (S=1/2) ions on the pyrochlore network. Synchrotron x-ray diffraction on a single crystal reveals a characteristic x-ray diffuse scattering (XDS) pattern primarily around q={0.5,0.5,2}. Reverse Monte Carlo (RMC) simulations uncover local Nb displacements along the ⟨111⟩ axes, leading to the formation of linear Nb_{4} tetramers. Our findings highlight a crucial role of molecular orbital degrees of freedom in stabilizing the nonmagnetic insulating state. This study demonstrates that RMC analysis of XDS provides a powerful approach for elucidating short-range correlations and the underlying mechanisms governing the physical properties of crystalline materials.
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