title: Crystal Structure and Magnetic Properties of [Cu(4-Me-3-Nit-trz)(4)](ClO(4))(2), with 4-Me-3-Nit-trz = 2-(3-[4-Methyl-1,2,4-triazolyl])-4,4,5,5-tetramethylimidazoline-1-oxyl 3-Oxide. Intra- and Intermolecular Spin Interactions.
abstract: The first two transition metal compounds incorporating triazole-nitronyl-nitroxide radicals as ligands have been synthesized. These compounds are [Cu(4-Me-3-Nit-trz)(4)](ClO(4))(2) (1) and [Ni(4-Me-3-Nit-trz)(4)](ClO(4))(2) (2) with 4-Me-3-Nit-trz = 2-(3-[4-methyl-1,2,4-triazolyl])-4,4,5,5-tetramethylimidazoline-1-oxyl 3-oxide. Compound 1 crystallizes in the triclinic system, space group P&onemacr;. The lattice parameters are a = 9.742(2) Å, b = 12.214(12) Å, c = 12.981(4) Å, alpha = 67.19(4) degrees, beta = 81.48(2) degrees, and gamma = 79.24(4) degrees, with Z = 1. The structure consists of centrosymmetrical [Cu(4-Me-3-Nit-trz)(4)]](2+)cations and noncoordinated perchlorate anions. The Cu(II) ion is in an N(4)O(2) elongated tetragonal environment with two oxygen atoms of two nitroxide groups occupying the apical positions. Within the lattice the cations form infinite chains with short intermolecular contacts involving the nitronyl-nitroxide moieties of two adjacents cations. The temperature dependence of the magnetic susceptibility and the field dependence of the magnetization at 2 K have been investigated. Both intermolecular antiferromagnetic and intramolecular ferromagnetic interactions are operative. A theoretical model has been developed to interpret quantitatively the magnetic data, which allows us to determine the values of the interaction parameters.
authors.affiliation: Laboratoire de Chimie Inorganique, URA CNRS No. 420, Université de Paris Sud, 91405 Orsay, France, Laboratoire des Sciences Moléculaires, Institut de Chimie de La Matière Condensée de Bordeaux, UPR CNRS No. 9048, Avenue du Docteur Schweitzer, 33608 Pessac, France, and Laboratoire de Chimie du Solide et Inorganique Moléculaire, URA CNRS No. 1495, Université de Rennes 1, 35042 Rennes, France.
authors.forename: Yu
authors.initials: Y
authors.lastname: Pei
authors.forename: Andreas
authors.initials: A
authors.lastname: Lang
authors.forename: Pierre
authors.initials: P
authors.lastname: Bergerat
authors.forename: Olivier
authors.initials: O
authors.lastname: Kahn
authors.forename: Mohammed
authors.initials: M
authors.lastname: Fettouhi
authors.forename: Lahcène
authors.initials: L
authors.lastname: Ouahab