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arXiv · 1102.3125

Helical magnetism and structural anomalies in triangular lattice α-SrCr2O4

S E Dutton·E Climent-Pascual·P W Stephens·J P Hodges·A Huq·C L Broholm·R J Cava
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Abstract

α-SrCr2O4 has a triangular planar lattice of d3 Cr3+ made from edge sharing CrO6 octahedra; the plane shows a very small orthorhombic distortion from hexagonal symmetry. With a Weiss temperature of -596 K and a three-dimensional magnetic ordering temperature of 43 K, the magnetic system is quasi two-dimensional and frustrated. Neutron powder diffraction shows that the ordered state is an incommensurate helical magnet, with an in-plane propagation vector of k = (0,0.3217(8),0). Temperature dependent synchrotron powder diffraction characterization of the structure shows an increase in the inter-plane spacing on cooling below 100 K and an inflection in the cell parameters at the magnetic ordering temperature. These anomalies indicate the presence of a moderate degree of magneto-structural coupling.

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S E Dutton, E Climent-Pascual, P W Stephens, J P Hodges, A Huq, C L Broholm, R J Cava. 2011-02-15. Helical magnetism and structural anomalies in triangular lattice α-SrCr2O4. https://doi.org/10.1088/0953-8984%2F23%2F24%2F246005

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