A new triclinic modification of the pyrochlore-type KOs2O6 superconductor

S. Katrych; Q. F. Gu; Z. Bukowski; N. D. Zhigadlo; G. Krauss; J. Karpinski

doi:10.1016/j.jssc.2008.11.003

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arXiv · 0811.4353

A new triclinic modification of the pyrochlore-type KOs2O6 superconductor

S. Katrych·Q. F. Gu·Z. Bukowski·N. D. Zhigadlo·G. Krauss·J. Karpinski

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Abstract

A new modification of KOs2O6, the representative of a new structural type (Pearson symbol aP18, a=5.5668(1)A, b=6.4519(2)A, c=7.2356(2)A, space group P-1, no.2) was synthesized employing high pressure technique. Its structure was determined by single-crystal X-ray diffraction. The structure can be described as two OsO6 octahedral chains relating to each other through inversion and forming big voids with K atoms inside. Quantum chemical calculations were performed on the novel compound and structurally related cubic compound. High-pressure X-ray study showed that cubic KOs2O6 phase was stable up to 32.5(2) GPa at room temperature.

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S. Katrych, Q. F. Gu, Z. Bukowski, N. D. Zhigadlo, G. Krauss, J. Karpinski. 2008-11-26. A new triclinic modification of the pyrochlore-type KOs2O6 superconductor. https://doi.org/10.1016/j.jssc.2008.11.003

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