Single Molecule Magnets

Ising-aniWe can rationally engineer and tune the Ising-type magnetic anisotropy in trigonal bipyramidal Co(II) complexes (and other low coordinate geometries). For example, we predicted that employing a ligand, which imposes a trigonal bipyramidal arrangement and has weak equatorial s-donating atoms, increases the negative zero field splitting parameter D. We synthesized and characterized a trigonal bipyramidal Co(II) complex, which was constructed from tris(2-(isopropylthio)ethyl)amine (NS3iPr). We showed that we can tune the magnitude of D by using our design principles and that we can considerably increase D (=-23 cm- 1 for [Co(NS3iPr)Cl](BPh4) by lengthening the bonds in the equatorial plane. The magnitude of the anisotropy parameters was experimentally determined and calculated using a correlated ab initio method.

Ln-SMMWe can employ the synthetic technique, subcomponent self-assembly, to construct molecules that show single molecule (SMM) behavior. We synthesized and studied six lanthanide (LnIII) containing complexes. The Ln(III) was used a template around which small commercial building blocks assembled. The complexes were isostructural. We could thus study how two effects influenced the magnetic propertied of the complexes: i) changing the metal ion, and ii) changing the electronic structure of the ligand. The central idea behind this work was to use a combination of experimental, and theoretical techniques to study how small modifications influence magnetic properties.


“Tuning the Ising-type anisotropy in trigonal bipyramidal Co(II) complexes.” F. Shao, B. Cahier, N. Guihéry, E. Riviere, R. Guillot, A.-L. Barra, Y. Lan, W. Wernsdorfer, V. E. Campbell,* and T. Mallah, Chem. Comm, 2015, 51, 16475-16478. Featured on the back cover.

“Assessing the exchange coupling in binuclear lanthanide(III) complexes and the slow relaxation of the magnetization in the antiferromagnetically coupled Dy2 derivative” C. Y. Chow, H. Bolvin, V. E. Campbell, R. Guillot, J. W. Kampf, H. Bolvin, W. Wernsdorfer, F. Gendrone, J. Autschbache, V. L. Pecoraro, and T. Mallah, Chem. Sci20156, 4148-4159.

“Chemical tuning of the Magnetic relazation in Dysprosium(III) mononuclear complexes” L. J. Batchelor, I. Cimatti, R. Guillot, F. Tuna, W. Wernsdorfer, L. R. Chibotaru, L. Ungur, V. E. Campbell, and T. Mallah, Dalton Trans.201443, 12146-12149.

“Structural and Electronic Dependence of the Magnetization in Dysprosium(III)-complexes” V. E. Campbell,* H. Bolvin, R. Guillot, E. Rivière, W. Wernsdorfer, and T. Mallah, Inorg. Chem2014. 53, 2598-2605

“Supcomponent Self-Assembly of Rare Earth Single Molecule Magnets” V. E. Campbell,* R. Guillot, E. Riviere, P.-T. Brun, W. Wernsdorfer, and T. Mallah, Inorg. Chem.201352, 5194-5200.