Séminaire du vendredi 23 novembre à 10H30

IMPMC, Université P. et M. Curie, 4, Place Jussieu, 75005 Paris

Salle de Conférence, 4ème étage, Tour 22-23, Salle 1

TOWARDS HIGH-TEMPERATURE SINGLE-MOLECULE MAGNETS

Vladimir S. MIRONOV A.V. Shubnikov Institute of Crystallography

Résumé :

The problem of high-temperature single-molecule magnets (SMM) is discussed. A promising approach is based on the use of molecular magnetic centers with unquenched orbital momentum. Very strong anisotropy of exchange interactions of such magnetic centers with attached high-spin 3d ions can be employed as a very efficient source of the molecular magnetic anisotropy of a SMM cluster. It is shown that orbitally-degenerate 4d and 5d complexes are the most promising for constructing high-T SMMs. Recent experimental results on SMM clusters based on Re^IV(CN)₇ ^3– and Os^III(CN)₆ ^3– complexes are overviewed and analyzed. New promising 4d and 5d orbitally degenerate molecular building blocks with macrocyclic ligands are presented Approaches and strategies for rational design SMM clusters with orbitally degenerate 4d and 5d complexes and tuning their magnetic characteristics are described and illustrated by representative examples. The prospect for designing SMM clusters with very high blocking temperature T_b (many tens K) is discussed.