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arXiv · 2410.09171

Selective synthesis and crystal chemistry of candidate rare earth Kitaev materials: honeycomb and hyperhoneycomb Na$_2$PrO$_3$

Ryutaro Okuma·Kylie MacFarquharson·Radu Coldea
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Abstract

Rare earth oxides have attracted interest as a platform for studying frustrated magnetism arising from bond dependent anisotropic interactions. Ordered rock salt compounds Na$_2$PrO$_3$ crystallize in two polymorphs ($\alpha$ and $\beta$) comprising honeycomb and hyperhoneycomb lattices of octahedrally coordinated Pr$^{4+}$ (4$f^1$). Although possible realization of antiferromagnetic Kitaev interactions is anticipated for these phases on the basis of ab initio models, the air-sensitivity of the two polymorphs has hampered reliable crystal growth and physical property measurements. Here, we have succeeded in preparing powder and single crystals of both $\alpha$- and $\beta$-Na$_2$PrO$_3$ using modified synthetic procedures. Revised crystal structures for both polymorphs are obtained from refinement of untwinned single-crystal X-ray diffraction data.

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Ryutaro Okuma, Kylie MacFarquharson, Radu Coldea. 2024-10-11. Selective synthesis and crystal chemistry of candidate rare earth Kitaev materials: honeycomb and hyperhoneycomb Na$_2$PrO$_3$. https://arxiv.org/abs/2410.09171

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