ChemInform Abstract: Giant Negative Thermal Expansion in the Iron Perovskite SrCu3Fe4O12.

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ChemInform 2011, 42, issue 40 © 2011 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim Thermal properties D 3000 DOI: 10.1002/chin.201140003 Giant Negative Thermal Expansion in the Iron Perovskite SrCu 3 Fe 4 O 12 . — Poly- crystalline SrCu3Fe4O12 is synthesized from a stoichiometric mixture of Sr(NO3)2, Cu(NO3)2, Fe(NO3)3, and a fivefold molar excess of citric acid dissolved in a mixture of water and ethanediol (433 K, 12 h) followed by decomposition of the resulting solid at 723 and 973 K. The obtained precursor is mixed with KClO4 and treated at 1273 K and 15 GPa for 15 min. SrCu 3 Fe 4 O 12 exhibits negative thermal expansion be- havior with a linear expansion coefficient of -2.26·10 -5 K -1 , which is comparable with the largest value reported to date. The large negative thermal expansion is explained by a strong internal compression of the Sr ion in the novel perovskite. The results demon- strate the strong influence of the A site cation in ACu3Fe4O12 perovskites on the elec- tronic and structural properties. — (YAMADA*, I.; et al.; Angew. Chem., Int. Ed. 50 (2011) 29, 6579-6582, http://dx.doi.org/10.1002/anie.201102228 ; Dep. Chem., Fac. Sci., Ehime Univ., Matsuyama, Ehime 790, Japan; Eng.) — W. Pewestorf 40- 003

Transcript of ChemInform Abstract: Giant Negative Thermal Expansion in the Iron Perovskite SrCu3Fe4O12.

Page 1: ChemInform Abstract: Giant Negative Thermal Expansion in the Iron Perovskite SrCu3Fe4O12.

Thermal propertiesD 3000 DOI: 10.1002/chin.201140003

Giant Negative Thermal Expansion in the Iron Perovskite SrCu3Fe4O12. — Poly-crystalline SrCu3Fe4O12 is synthesized from a stoichiometric mixture of Sr(NO3)2, Cu(NO3)2, Fe(NO3)3, and a fivefold molar excess of citric acid dissolved in a mixture of water and ethanediol (433 K, ≈12 h) followed by decomposition of the resulting solid at 723 and 973 K. The obtained precursor is mixed with KClO4 and treated at 1273 K and 15 GPa for 15 min. SrCu3Fe4O12 exhibits negative thermal expansion be-havior with a linear expansion coefficient of -2.26·10-5 K-1, which is comparable with the largest value reported to date. The large negative thermal expansion is explained by a strong internal compression of the Sr ion in the novel perovskite. The results demon-strate the strong influence of the A site cation in ACu3Fe4O12 perovskites on the elec-tronic and structural properties. — (YAMADA*, I.; et al.; Angew. Chem., Int. Ed. 50 (2011) 29, 6579-6582, http://dx.doi.org/10.1002/anie.201102228 ; Dep. Chem., Fac. Sci., Ehime Univ., Matsuyama, Ehime 790, Japan; Eng.) — W. Pewestorf

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ChemInform 2011, 42, issue 40 © 2011 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim