Skip to main content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Crystallographic Studies of Ba12Nb8-xTaxCo4O36 (x=1,3,4,5,7)

Published

Author(s)

Winnie K. Wong-Ng, Guangyao Liu, Igor Levin, Izaak Williamson, James A. Kaduk, Lan Li, Andres C. Hernandez

Abstract

Crystal structures and X-ray reference powder diffraction patterns have been determined for the Ba12Nb8-xTaxCo4O36 (x = 1, 3, 4, 5, 7) series. Ba12Nb8-xTaxCo4O36 crystallize in the cubic perovskite structure with a space group Pm3m (No. 221) and the lattice parameter increasing from a = 4.08732(3) Å to a = 4.08894 (2) Å as x varies from 1 to 7. The Goldschmidt distortion parameter for the entire series is about 1.05 (1.0488 to 1.0506), being similar to that of the cubic end member BaNb2CoO12. Transmission electron microscopy of the composition Ba12Nb4Ta4Co4O36 (or Ba3(NbTaCo)O9) revealed nanoscale 1:2 ordering of Nb/Ta and Co, manifested in the presence of the diffuse superlattice reflections. As this ordering is limited to short range, the average structures were still refined assuming the ideal-perovskite cubic symmetry. X-ray powder diffraction patterns of the studied compounds have been submitted to the Powder Diffraction File (PDF).
Citation
Powder Diffraction
Volume
71

Keywords

X-ray diffraction patterns, crystal structure, Ba12Nb8-xTaxCo4O36, Powder Diffraction File (PDF), TEM studies, short-range 1:2 ordering.
Created July 21, 2017, Updated March 24, 2019