Record Details
True Composition and Structure of Hexagonal “YAlO₃”, Actually Y₃Al₃O₈CO₃
ScholarsArchive at Oregon State University
| Field | Value |
|---|---|
| Title | True Composition and Structure of Hexagonal “YAlO₃”, Actually Y₃Al₃O₈CO₃ |
| Names |
Li, Jun
(creator) Sinith, Andrew E. (creator) Jiang, Peng (creator) Stalick, Judith K. (creator) Sleight, Arthur W. (creator) Subramanian, M. A. (creator) |
| Date Issued | 2014-10-31 (iso8601) |
| Note | To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by the American Chemical Society and can be found at: http://pubs.acs.org/journal/inocaj. |
| Abstract | The discovery of a brilliant-blue color upon the introduction of Mn³⁺ to the trigonal-bipyramidal (TBP) sites in YInO₃ has led to a search for other hosts for Mn³⁺ in TBP coordination. An obvious choice would be YAlO₃. This compound, which has only been prepared through a citrate precursor route, has long been considered isostructural with YAlO₃. However, Mn³⁺ substitutions into YAlO₃ have failed to produce a product with the anticipated color. We find that the hexagonal structure for YAlO₃ with Al in TBP coordination proposed in 1963 cannot be correct based on its unit cell dimensions and bond-valence sums. Our studies indicate instead that all, or nearly all, of the Al in this compound has a coordination number (CN) of 6. Upon heating in air, this compound transforms to YAlO₃, with the perovskite structure liberating CO₂. The compound long assumed to be a hexagonal form of YAlO₃ is actually an oxycarbonate with the ideal composition Y₃Al₃O₈CO₃. The structure of this compound has been characterized by powder neutron and X-ray diffraction data obtained as a function of temperature, magic-angle-spinning ²⁷Al NMR, Fourier transform infrared, and transmission electron microscopy. Refinement of neutron diffraction data indicates a composition of Y₃Al₃O₈CO₃. We find that the hexagonal structures of YGaO₃ and YFeO₃ from the citrate route are also stabilized by small amounts of carbonate. Surprisingly, Y₃Al₃O₈CO₃ forms a complete solid solution with YBO₃ having tetrahedral borate groups. Other unlikely solid solutions were prepared in the YAlO₃−YMnO₃, YAlO₃−YFeO₃, YAlO₃−YBO₃, YBO₃−YMnO₃, YBO₃−YFeO₃, and YBO₃−YGaO₃ systems. |
| Genre | Article |
| Identifier | Li, J., Smith, A. E., Jiang, P., Stalick, J. K., Sleight, A. W., & Subramanian, M. A. (2014). True Composition and Structure of Hexagonal “YAlO₃”, Actually Y₃Al₃O₈CO₃. Inorganic Chemistry, 54(3), 837-844. doi:10.1021/ic502027k |
