title: New topology in azide-bridged cobalt(II) complexes: the weak ferromagnet [Co(2)(N(3))(4)(Hexamethylenetetramine)(H(2)O)](n).
abstract: A new polynuclear azido-bridged Co(II) compound with formula [Co(2)(N(3))(4)(HMTA)(H(2)O)](n) (1) (HMTA = hexamethylenetetramine) has been structurally and magnetically characterized. The compound 1 crystallizes in the monoclinic system C2/m space group, and consist of a complex three-dimensional system in which end-to-end and end-on azido bridging ligands between the Co(II) atoms coexist. The HMTA ligand is also linking three different Co(II) atoms. The network analysis shows for 1 a three- and six-connected network topology not previously reported. The magnetic properties of 1 are also reported, and it was found that the magnetic interactions define another new three- and four-connected net assigned as a (6.8(2))(6(4).10(2))-tfo net. In the high temperature region the chi(M) versus T plot can be fitted by using the Curie-Weiss law, and the best fit theta value is -26.6 K. For 1 magnetic ordering and spontaneous magnetization is achieved below T(c) = 15.6 K.
authors.affiliation: Institut für Physikalische und Theoretische Chemie, Technische Universität Graz, Rechbauerstrasse 12, A-8010, Graz, Austria.
authors.forename: Franz A
authors.initials: FA
authors.lastname: Mautner
authors.forename: Lars
authors.initials: L
authors.lastname: Ohrström
authors.forename: Beate
authors.initials: B
authors.lastname: Sodin
authors.forename: Ramon
authors.initials: R
authors.lastname: Vicente