Ba3YRu0.73(2)Al1.27(2)O8 and Ba5Y2Ru1.52(2)Al1.47(2)O13.5: New Perovskite Ruthenates with Partial Octahedra Replacement

• Published in: Zeitschrift für Naturforschung. B, A journal of chemical sciences Vol. 62; no. 11; pp. 1383 - 1389
• Main Authors: Schüpp-Niewaa, Barbara, Shlyk, Larysa, Prots, Yurii, Krabbes, Gernot, Niewa, Rainer
• Format: Journal Article
• Language: English
• Published: Verlag der Zeitschrift für Naturforschung 01-11-2007
• Subjects: Crystal Structure; Perovskite; Ruthenium; Solid State Synthesis
• ISSN: 0932-0776; 1865-7117
• DOI: 10.1515/znb-2007-1106

Dark red single crystals of the new phases Ba
YRu
Al
and Ba
Ru
Al
have been grown from powder mixtures of BaCO
, Y
, Al
, and RuO
. The compositions given in the formulas result from the refinements of the crystal structures based on single crystal X-ray diffraction data (hexagonal P6
/mmc (No. 194), Z = 2, Ba
YRu
Al
: a = 5.871(1), c = 14.633(3) Å , R1 = 0.035, wR2 = 0.069 and Ba
Ru
Al
: a = 5.907(1), c = 24.556(5) Å, R1 = 0.057, wR2 = 0.114). Ba
YRu
Al
crystallizes in a 6H perovskite structure, Ba
Ru
Al
has been characterized as a 10H Perovskite. Due to similar spatial extensions of (Ru
) facesharing pairs of octahedra and (Al
) vertex-sharing pairs of tetrahedra, both structures show partial mutual substitution of these units. Consequently, the title compounds may be written as Ba
Y(Ru
(Al
, x = 0.64(1) and Ba
RuO
(Ru
(Al
, x = 0.74(1). This interpretation is supported by the results of electron probe microanalysis using wavelength-dispersive X-ray spectroscopy. An oxidation state of Ru close to +5 for the (Ru
) units, as can be derived from the distances d(Ru-Ru), additionally leads to similar charges of both the (Ru
) and the (Al
) units.