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arXiv · 1101.2847

Magnetic Frustration in a Mn Honeycomb Lattice Induced by Mn-O-O-Mn Pathways

H. Wadati·K. Kato·Y. Wakisaka·T. Sudayama·D. G. Hawthorn·T. Z. Regier·N. Onishi·M. Azuma·Y. Shimakawa·T. Mizokawa·A. Tanaka·G. A. Sawatzky
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Abstract

We investigated the electronic structure of layered Mn oxide Bi3Mn4O12(NO3) with a Mn honeycomb lattice by x-ray absorption spectroscopy. The valence of Mn was determined to be 4+ with a small charge-transfer energy. We estimated the values of superexchange interactions up to the fourth nearest neighbors (J1, J2, J3, and J4) by unrestricted Hartree-Fock calculations and a perturbation method. We found that the absolute values of J1 through J4 are similar with positive (antiferromagnetic) J1 and J4, and negative (ferromagnetic) J2 and J3, due to Mn-O-O-Mn pathways activated by the smallness of charge-transfer energy. The negative J3 provides magnetic frustration in the honeycomb lattice to prevent long-range ordering.

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H. Wadati, K. Kato, Y. Wakisaka, T. Sudayama, D. G. Hawthorn, T. Z. Regier, N. Onishi, M. Azuma, Y. Shimakawa, T. Mizokawa, A. Tanaka, G. A. Sawatzky. 2011-01-14. Magnetic Frustration in a Mn Honeycomb Lattice Induced by Mn-O-O-Mn Pathways. https://doi.org/10.1016/j.ssc.2013.02.021

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