title: Nickel(II) chain with alternating end-on/end-to-end single azido bridges: a combined structural, magnetic, and theoretical study.
abstract: The reaction of a tridentate Schiff base LH (L-: 1,1,1-trifluoro-7-(dimethylamino)-4-methyl-5-aza-3-hepten-2-onato) with a Ni(II) salt in the presence of azide salt has led to a new alternating end-on (EO)/end-to-end (EE) azido-bridged Ni(II) chain of formula {[Ni2(micro1,1-N3)(micro1,3-N3)(L)2(MeOH)2]}n. Its originality lies in the presence of single EE and EO coordination modes for the azide. It crystallizes in the C2/c space group, a=21.570(7) A, b=10.79(1) A, c=16.154(5) A, beta=120.81(2) degrees, Z=4. The chain can be viewed as {Ni2(N3)(L)2(MeOH)2}+ dimeric units linked to each other in a zigzag pattern by the other azide. Magnetic susceptibility and magnetization measurements have been performed and revealed that the chain can magnetically be depicted as isolated {Ni2(N3)} units exhibiting antiferromagnetic interaction (JAF approximately -37 cm(-1)). Ab initio calculations confirmed the efficient magnetic coupling through the EE bridge and vanishingly small EO {Ni2(micro1,1-N3)} interactions.
authors.affiliation: Laboratoire de Chimie (UMR 5182), Ecole Normale Supérieure de Lyon, 46 allée d'Italie, 69364 Lyon cedex 07, France.
authors.forename: Marie-Laure
authors.initials: ML
authors.lastname: Bonnet
authors.forename: Christophe
authors.initials: C
authors.lastname: Aronica
authors.forename: Guillaume
authors.initials: G
authors.lastname: Chastanet
authors.forename: Guillaume
authors.initials: G
authors.lastname: Pilet
authors.forename: Dominique
authors.initials: D
authors.lastname: Luneau
authors.forename: Corine
authors.initials: C
authors.lastname: Mathonière
authors.forename: Rodolphe
authors.initials: R
authors.lastname: Clérac
authors.forename: Vincent
authors.initials: V
authors.lastname: Robert