Structure and X-ray Reference diffraction patterns of (Ba6-xSrx)R2Co4O15 (x=1, 2) (R=Lanthanides)

Published

February 4, 2014

Author(s)

Winnie K. Wong-Ng, Guangyao Liu, Yonggao Y. Yan, James A. Kaduk

Abstract

The structure and X-ray patterns of two series of barium lanthanide cobaltites, namely, Ba4Sr2R2Co4O15 (R=La, Nd, Sm, Eu, Gd, Dy), and Ba5SrR2Co4O15 (R= La, Nd, Sm, Eu, and Gd) have been determined. These compounds crystallize in the space group P63mc; the cell parameters of Ba4Sr2R2Co4O15 (R from La to Dy) decrease from a=11.6128(2) Å to 11. 5266(9) Å, c = 6.86903(11) to 6. 7630(5) Å, and V=802.23(3) Å3 to 778.17(15) Å3, respectively. In the Ba5SrR2Co4O15 series (R=La to Gd), the cell parameters decrease from a= 11.73544(14) Å to 11.61979(12) Å, c= 6.94289 (14) Å to 6.83652(8) Å, and V= 828.08(3) Å3 to 799.40(2) Å3. In the general structure of (Ba6-xSrx)R2Co4O15, there are four Co ions per formula unit occupying one CoO6 octahedral and three CoO4 tetrahedral units. Through corner-sharing of these polyhedra, a larger Co4O15 unit is formed. Sr2+ ions adopt both octahedral and 8-fold coordination environment. R3+ ions adopt 8-fold coordination (mixed site with Sr) while the larger Ba2+ ions assume both 10- and 11-fold coordination environment. X-ray diffraction patterns of these samples have been determined and submitted to the Powder Diffraction File (PDF).

Citation

Powder Diffraction

Volume

28

Issue

3

Pub Type

Journals

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DOI Link

Keywords

X-ray reference diffraction patterns, (Ba6-xSrx)R2Co4O15 (x=1, 2) (R=La, Nd, Sm, Eu, and Gd), crystal structure

Citation

Wong-Ng, W. , Liu, G. , Yan, Y. and Kaduk, J. (2014), Structure and X-ray Reference diffraction patterns of (Ba6-xSrx)R2Co4O15 (x=1, 2) (R=Lanthanides), Powder Diffraction, [online], https://doi.org/10.1017/S0885715613000171 (Accessed April 19, 2024)