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arXiv · 0706.1468

Enhanced Pressure Dependence of Magnetic Exchange in A2+[V2]O4 Spinels Approaching the Itinerant Electron Limit

S. Blanco-Canosa·F. Rivadulla·V. Pardo·D. Baldomir·J. -S. Zhou·M. Garcia-Hernandez·M. A. Lopez-Quintela·J. Rivas·J. B. Goodenough
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Abstract

We report a systematic enhancement of the pressure dependence of TN in A2+[V2]O4 spinels as the V-V separation approaches the critical separation for a transition to itinerant-electron behavior. An intermediate phase between localized and itinerant electron behavior is identified in Zn[V2]O4 and Mg[V2]O4 exhibiting mobile holes as large polarons. In Zn[V2]O4, cooperative ordering of V-V pairs below a Ts=TN does not totally suppress the V3+-ion spins at ambient pressure, but makes TN to decrease with pressure. Our results demonstrate that Zn[V2]O4 and Mg[V2]O4 are less localized than previously thought.

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S. Blanco-Canosa, F. Rivadulla, V. Pardo, D. Baldomir, J. -S. Zhou, M. Garcia-Hernandez, M. A. Lopez-Quintela, J. Rivas, J. B. Goodenough. 2007-06-11. Enhanced Pressure Dependence of Magnetic Exchange in A2+[V2]O4 Spinels Approaching the Itinerant Electron Limit. https://doi.org/10.1103/physrevlett.99.187201

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