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Spin gap formation in the quantum spin systems TiOX, X=Cl and Br

P. Lemmens·K. Y. Choi·R. Valenti·T. Saha-Dasgupta·E. Abel·Y. S. Lee·F. C. Chou
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Abstract

In the layered quantum spin systems TiOCl and TiOBr the magnetic susceptibility shows a very weak temperature dependence at high temperatures and transition-induced phenomena at low temperatures. There is a clear connection of the observed transition temperatures to the distortion of the octahedra and the layer separation. Band structure calculations point to a relation of the local coordinations and the dimensionality of the magnetic properties. While from magnetic Raman scattering only a small decrease of the magnetic exchange by -5-10% is derived comparing TiOCl with TiOBr, the temperature dependence of the magnetic susceptibility favors a much bigger change.

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P. Lemmens, K. Y. Choi, R. Valenti, T. Saha-Dasgupta, E. Abel, Y. S. Lee, F. C. Chou. 2005-01-24. Spin gap formation in the quantum spin systems TiOX, X=Cl and Br. https://doi.org/10.1088/1367-2630%2F7%2F1%2F074

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