Some polynuclear transition metal complexes, known as single molecule magnets (SMM), show a slow relaxation of the magnetization and, as a result, each individual molecule behaves as a magnet. Hence, SMM's have been proposed either as potential materials for information storage at the molecular level or as qubits in quantum computers, due to their quantum-controlled spin flip. In this field, the Holy Grail is an SMM with a high enough spin inversion barrier to avoid both the thermal spin flip and quantum tunneling effects. The synthesis of new SMMs is a serendipitous search for large energy barriers (large total spin and large and negative magnetic anisotropy). However, theoretical methods allow us to understand and rationalize the experimental data and to point out new synthetic targets. The use of electronic structure calculations allows to determine all the exchange coupling constants present in the same as well as the magnetic anisotropy that is usually quantified by means of the zero-field splitting parameters. Also, low-spin magnetic molecules have been also proposed as molecular qubits. Our research is focusing on the spin relaxation properties of such systems, in order to extract qualitative predictions about the coherence time of such systems. In our group, we are performing both the theoretical studies and the experimental synthesis and characterization of SMM systems.
M. Ding, G. E. Cutsail III, D. Aravena, D.; M. Amoza, M. Rouzieres, P. Dechambenoit, Y. Losovyj, M. Pink, E. Ruiz, R. Clérac and J. M. Smith. "A low spin manganese(iv) nitride single molecule magnet." Chem. Sci.2016, 7, 6132-6140. Doi: 10.1039/C6SC01469K
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