title: Ising-type Magnetic Anisotropy and Slow Relaxation of the Magnetization in Four-Coordinate Amido-Pyridine FeIIComplexes.
abstract: A family of four-coordinate FeIIcomplexes formed with N,N'-chelating amido-pyridine ligands was synthesized, and their magnetic properties were investigated. These distorted tetrahedral complexes exhibit significant magnetic anisotropy with zero-field splitting parameter D ranging between -17 and -12 cm-1. Ab initio calculations enabled identification of the structural factors that control the nature of the magnetic anisotropy and the rationalization of the variation of D in these complexes. It is shown that a reduced N-Fe-N angle involving the chelating nitrogen atoms of the ligands is at the origin of the negative D value and that the torsion between the two N-Fe-N planes imposed by steric hindrances further increases the |D| value. Field-induced slow relaxation of magnetization was observed for the three compounds, and a single-molecule magnet behavior with an energy barrier for magnetization flipping (Ueff) of 27 cm-1could be evidenced for one of them.
authors: CNRS, LCC , 205 route de Narbonne, F-31077 Toulouse, France.|Université de Toulouse, UPS, INPT, LCC , F-31007 Toulouse, France.
authors: C Gunnar
authors: CG
authors: Werncke
authors: LCPQ, Université de Toulouse III , 118 route de Narbonne, F-31062 Toulouse, France.
authors: Mohammed-Amine
authors: MA
authors: Bouammali
authors: LCPQ, Université de Toulouse III , 118 route de Narbonne, F-31062 Toulouse, France.
authors: Julie
authors: J
authors: Baumard
authors: LCPQ, Université de Toulouse III , 118 route de Narbonne, F-31062 Toulouse, France.
authors: Nicolas
authors: N
authors: Suaud
authors: LCPQ, Université de Toulouse III , 118 route de Narbonne, F-31062 Toulouse, France.
authors: Cyril
authors: C
authors: Martins
authors: LCPQ, Université de Toulouse III , 118 route de Narbonne, F-31062 Toulouse, France.
authors: Nathalie
authors: N
authors: Guihéry
authors: CNRS, LCC , 205 route de Narbonne, F-31077 Toulouse, France.|Université de Toulouse, UPS, INPT, LCC , F-31007 Toulouse, France.
authors: Laure
authors: L
authors: Vendier
authors: Team Organometallics: Materials and Catalysis, Centre for Catalysis and Green Chemistry, Campus de Beaulieu, Institut des Sciences Chimiques de Rennes, UMR 6226 CNRS-Université de Rennes 1 , 263 av. du Général Leclerc, F-35042 Rennes Cedex, France.
authors: Jianxia
authors: J
authors: Zheng
authors: Team Organometallics: Materials and Catalysis, Centre for Catalysis and Green Chemistry, Campus de Beaulieu, Institut des Sciences Chimiques de Rennes, UMR 6226 CNRS-Université de Rennes 1 , 263 av. du Général Leclerc, F-35042 Rennes Cedex, France.
authors: Jean-Baptiste
authors: JB
authors: Sortais
authors: Team Organometallics: Materials and Catalysis, Centre for Catalysis and Green Chemistry, Campus de Beaulieu, Institut des Sciences Chimiques de Rennes, UMR 6226 CNRS-Université de Rennes 1 , 263 av. du Général Leclerc, F-35042 Rennes Cedex, France.
authors: Christophe
authors: C
authors: Darcel
authors: CNRS, LCC , 205 route de Narbonne, F-31077 Toulouse, France.|Université de Toulouse, UPS, INPT, LCC , F-31007 Toulouse, France.
authors: Sylviane
authors: S
authors: Sabo-Etienne
authors: CNRS, LCC , 205 route de Narbonne, F-31077 Toulouse, France.|Université de Toulouse, UPS, INPT, LCC , F-31007 Toulouse, France.
authors: Jean-Pascal
authors: JP
authors: Sutter
authors: CNRS, LCC , 205 route de Narbonne, F-31077 Toulouse, France.|Université de Toulouse, UPS, INPT, LCC , F-31007 Toulouse, France.
authors: Sébastien
authors: S
authors: Bontemps
authors: CNRS, LCC , 205 route de Narbonne, F-31077 Toulouse, France.|Université de Toulouse, UPS, INPT, LCC , F-31007 Toulouse, France.
authors: Céline
authors: C
authors: Pichon