Abstract
Single crystals of BaRuO3were grown using a BaCl2flux at ambient pressure. Most of the crystals had the nine-layer rhombohedral structure (9R) which is considered to be the stable form of BaRuO3at ambient pressure. However, some BaRuO3crystals in this preparation had the four-layer hexagonal (4H) structure which had been considered as a phase produced only at high pressure (15-30 kbar). The crystal structure of 4H BaRuO3was refined for the first time. Single crystal X-ray diffraction data gave a space group ofP63/mmc(No. 194),a=5.729(1) Å,c=9.500(1) Å,Z=4, a final conventionalR(based onF0) of 2.01%, and awR2 (based onF20) of 4.07%. The structure of 4H BaRuO3may be described as perovskite-related with a four-layer stacking of BaO3layers in the sequencehchc. This leads to pairs of face-sharing RuO6octahedra which are connected to other octahedra by corner sharing. The Ru-Ru distance in the Ru2O9dimer of 4H BaRuO3is 2.537(1) Å which indicates the presence of a metal-metal bond.
Original language | English |
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Pages (from-to) | 251-255 |
Number of pages | 5 |
Journal | Journal of Solid State Chemistry |
Volume | 128 |
Issue number | 2 |
DOIs | |
State | Published - 1 Feb 1997 |
Bibliographical note
Funding Information:This work was supported by NSF Grant DMR-9308530.