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Control and Transferability of Magnetic Interactions in Supramolecular Structures: Trimers of {Cr7 Ni}
Selena J Lockyer1, Deepak Asthana1, George F S Whitehead1
1Department of Chemistry, The University of Manchester, Oxford Road, Manchester, M13 9PL, United Kingdom.
Abstract:
A synthetic strategy is demonstrated to prepare two distinct trimers of antiferromagnetically coupled {Cr7 Ni} rings, substantially varying the magnetic interactions between the spin centres. The interactions were studied using multi-frequency cw EPR: in a trimer linked via non-covalent H-bonding interactions no measurable interaction between rings was seen, while in a trimer linked via iso-nicotinate groups isotropic and anisotropic exchange interactions of +0.42 and -0.8 GHz, respectively, were observed. The latter are the same as those for a simpler hetero-dimer system, showing how the spin-spin interactions can be built in a predictable and modular manner in these systems.
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