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NaCa4Nb5O17: a layered perovskite AnBnO3n+2 compound
1Institut de Cristallographie, Université de Lausanne, BSP Dorigny 1015 Lausanne, Switzerland. wmpzulaj@lg.ehu.es
Acta Crystallographica. Section C, Crystal Structure Communications
|February 8, 2003
Summary
Sodium tetracalcium pentaniobium heptadecaoxide (NaCa(4)Nb(5)O(17)) exhibits a unique perovskite structure with n=5 blocks. This study details its structural characteristics and atomic site preferences within the homologous A(n)B(n)O(3n+2) family.
Area of Science:
- Solid-state chemistry
- Crystallography
- Materials science
Background:
- The A(n)B(n)O(3n+2) family represents homologous structures derived from perovskite layers.
- Understanding the structural variations within this family is crucial for materials design.
Purpose of the Study:
- To elucidate the crystal structure of sodium tetracalcium pentaniobium heptadecaoxide (NaCa(4)Nb(5)O(17)).
- To analyze the arrangement and coordination of atoms within the n=5 member of the A(n)B(n)O(3n+2) homologous series.
Main Methods:
- Crystallographic analysis of NaCa(4)Nb(5)O(17).
- Detailed examination of the perovskite-type blocks and interblock regions.
Main Results:
- NaCa(4)Nb(5)O(17) features perovskite blocks of n=5 NbO(6) octahedra, separated by interblock regions.
- Octahedral deformation varies within blocks, being minimal centrally and maximal at the ends.
- Sodium and calcium atoms occupy intrablock sites with 12-oxygen coordination, while calcium exclusively occupies interblock sites with varying coordination.
Conclusions:
- The study provides a detailed structural description of NaCa(4)Nb(5)O(17).
- The findings contribute to the understanding of structure-property relationships in the A(n)B(n)O(3n+2) homologous series.
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