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Magnetic properties of a metal-organic antiferromagnet on a distorted honeycomb lattice

Ivan Spremo·Florian Schuetz·Peter Kopietz·Volodymyr Pashchenko·Bernd Wolf·Michael Lang·Jan W. Bats·Chunhua Hu·Martin U. Schmidt
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Abstract

For temperatures T well above the ordering temperature T*=3.0+-0.2K the magnetic properties of the metal-organic material Mn[C10H6(OH)(COO)]2x2H20 built from Mn^2+ ions and 3-hydroxy-2-naphthoic anions can be described by a S=5/2 quantum antiferromagnet on a distorted honeycomb lattice with two different nearest neighbor exchange couplings J2 \approx 2J1 \approx 1.8K. Measurements of the magnetization M(H,T) as a function of a uniform external field H and of the uniform zero field susceptibility χ(T) are explained within the framework of a modified spin-wave approach which takes into account the absence of a spontaneous staggered magnetization at finite temperatures.

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Ivan Spremo, Florian Schuetz, Peter Kopietz, Volodymyr Pashchenko, Bernd Wolf, Michael Lang, Jan W. Bats, Chunhua Hu, Martin U. Schmidt. 2005-08-23. Magnetic properties of a metal-organic antiferromagnet on a distorted honeycomb lattice. https://doi.org/10.1103/physrevb.72.174429

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