Tetranuclear [Cu-Ln]2 single molecule magnets: synthesis, structural and magnetic studies.
A trianionic ligand H3L (2-hydroxy-N-(2-[[(2-hydroxyphenyl)methylene]amino]-2-methylpropyl)benzamide) with an inner N2O2 coordination site and an oxygen atom coming from an amide function not involved in this site yields monoanionic LCu- complexes that react with Ln(hfa)3 x 2H2O (hfa = hexafluoroacetylacetonato ligand) to give dinuclear Cu-Ln complexes that self-assemble into tetranuclear species, as demonstrated by the structural determination of the [LCuDy(hfa)2(dmf)2]2 complex. High-spin species are then isolated for two ferromagnetic interactions are active in the [Cu-Gd]2 entities, through the double phenoxo bridge (J = 3.2 cm(-1)) and through the single amide bridge (j = 0.54 cm(-1)). These interactions are still present in the [Cu-Tb]2 and [Cu-Dy]2 complexes which behave as single molecule magnets (SMMs), due to the introduction of anisotropic Ln ions in place of Gd ions.
Costes
Jean-Pierre
JP
Laboratoire de Chimie de Coordination du CNRS, UPR 8241, liée par conventions à l'Université Paul Sabatier et àl'Institut National Polytechnique de Toulouse, 205 route de Narbonne, 31077, Toulouse, Cedex, France. costes@lcc-toulouse.fr
Shova
Sergiu
S
Wernsdorfer
Wolfgang
W
D001549:Benzamides / Q000737:chemistry*; D003300:Copper / Q000737:chemistry*; D018360:Crystallography, X-Ray; D028581:Lanthanoid Series Elements / Q000737:chemistry*; D008024:Ligands; D008280:Magnetics; D008958:Models, Molecular; D015394:Molecular Structure; D009589:Nitrogen Oxides / Q000737:chemistry; D009942:Organometallic Compounds / Q000138:chemical synthesis* / Q000737:chemistry*; D013696:Temperature
D001549:Benzamides; D028581:Lanthanoid Series Elements; D008024:Ligands; D009589:Nitrogen Oxides; D009942:Organometallic Compounds; D003300:Copper