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Supramolecular Co(II)-[2 x 2] grids: Metamagnetic behavior in a single molecule

O. Waldmann·M. Ruben·U. Ziener·P. Müller·J. M. Lehn
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Abstract

The magnetic anisotropy of the supramolecular [2 x 2] grid [Co(II)4L4]8+, with a bis(bipyridyl)-pyrimidine based ligand L, was investigated by single-crystal magnetization measurements at low temperatures. The magnetization curves exhibit metamagnetic like behavior and are explained by the weak-exchange limit of a minimal spin Hamiltonian including Heisenberg exchange, easy-axis ligand fields, and the Zeeman term. It is also shown that the magnetic coupling strength can be varied by the substituent R1 in the 2-position on the central pyrimidine group of the ligand L.

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O. Waldmann, M. Ruben, U. Ziener, P. Müller, J. M. Lehn. 2006-06-15. Supramolecular Co(II)-[2 x 2] grids: Metamagnetic behavior in a single molecule. https://arxiv.org/abs/cond-mat/0606422

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