Single molecule magnet behaviour and luminescence in Ln(III) complexes based on redox active ligands derived from TTFs

Copyright (C) 2014 American Chemical Society (ACS). All Rights Reserved.; International audience; In the last decade, TTF derivs. have been assocd. to d metal ions to elaborate multifunctional materials which possess magnetic and elec. properties. The 4f lanthanides exhibit exiting specific luminescent properties. In particular, lanthanide complexes with b-diketones have focused a large attention due to their potential applications in the design of chelate lasers, efficient org. and polymer light emitting diodes (OLEDs and PLEDs). The irradn. of the [Yb(hfac)3(TTF-CONH-2-Py-N-oxide)2] compd. in the HOMO-LUMO+1/+2 charge transfer bands provokes the emission of both donor and Yb(III) ion. We have shown that the donor is an efficient org. antenna for the sensitization of Yb(III) luminescence in both solid state while the Er(III) show the luminescence property in soln. Lanthanide ions are also well-known to exhibit strong magnetic anisotropy and so they are considered as good candidates for the elaboration of Single Mol. Magnets (SMM). We have assocd. the tetrathiafulvalene-3-Pyridine-N-oxide ligand to the Ising Dy(III) ions producing a centrosym. dinuclear complex in which the magnetic moments are antiferromagnetically coupled. Surprisingly, the complex behaves as a SMM with strong frequency dependent out-of-phase signal of the ac magnetic susceptibility. A new Single Ion Magnet (SIM) was also recently discovered in the Dy2 dimers contg. a A-D-A bridge. [on SciFinder(R)]