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arXiv · 0708.2088

Insulator to semiconductor transition and magnetic properties of the one-dimensional S = 1/2 system In_2VO_5

A. Moller·T. Taetz·N. Hollmann·J. A. Mydosh·V. Kataev·M. Yehia·E. Vavilova·B. Buchner
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Abstract

We report structural, magnetization, electrical resistivity and nuclear- and electron spin resonance data of the complex transition metal oxide In_2VO_5 in which structurally well-defined V-O chains are realized. An itinerant character of the vanadium d-electrons and ferromagnetic correlations, revealed at high temperatures, are contrasted with the insulating behavior and predominantly antiferromagnetic exchange between the localized V^{4+} S = 1/2-magnetic moments which develop below a certain characteristic temperature T* ~ 120 K. Eventually the compound exhibits short-range magnetic order at $T_SRO ~ 20 K. We attribute this crossover occurring around T* to the unusual anisotropic thermal contraction of the lattice which changes significantly the overlap integrals and the character of magnetic intra- and interchain interactions.

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A. Moller, T. Taetz, N. Hollmann, J. A. Mydosh, V. Kataev, M. Yehia, E. Vavilova, B. Buchner. 2007-08-15. Insulator to semiconductor transition and magnetic properties of the one-dimensional S = 1/2 system In_2VO_5. https://doi.org/10.1103/physrevb.76.134411

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