title: Two oxo complexes with tetranuclear [Fe(4)(mu(3)-O)(2)](8+) and trinuclear [Fe(3)(mu(3)-O)](7+) units.
abstract: Two new oxo complexes, namely hexa-mu(2)-acetato-acetatoaquabis(di-3-pyridylamine)di-mu(3)-oxo-tetrairon(III) chloride monohydrate ethanol 1.25-solvate, [Fe(4)(C(2)H(3)O(2))(7)O(2)(C(10)H(9)N(3))(2)(H(2)O)]Clx1.25C(2)H(6)OxH(2)O, (I), containing a tetranuclear [Fe(4)(mu(3)-O)(2)](8+) unit, and 2-methylimidazolium hexa-mu(2)-acetato-acetatodiaqua-mu(3)-oxo-triiron(III) chloride dihydrate, (C(4)H(7)N(2))[Fe(3)(C(2)H(3)O(2))(7)O(H(2)O)(2)]Clx2H(2)O, (II), with a trinuclear [Fe(3)(mu(3)-O)](7+) unit, are presented. Both structures are formed by two well differentiated entities, viz. a compact isolated cluster composed of Fe(III) ions coordinated to O(2-) and CH(3)CO(2)(-) anions, and an external group formed by a central Cl(-) ion surrounded by different solvent groups to which the anion is bound through hydrogen bonding. In the case of (I), charge balance cannot be achieved within the groups, so the structure is macroscopically ionic; in the case of (II), in contrast, each group is locally neutral owing to the internal compensation of charges. The trinuclear complex crystallizes with the metal cluster, chloride anion and 2-methylimidazolium cation bisected by a crystallographic mirror plane.
authors.affiliation: Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile. pcortes@ciq.uchile.cl
authors.forename: Piedad
authors.initials: P
authors.lastname: Cortés
authors.forename: Ana María
authors.initials: AM
authors.lastname: Atria
authors.forename: María Teresa
authors.initials: MT
authors.lastname: Garland
authors.forename: Ricardo
authors.initials: R
authors.lastname: Baggio
mesh_terms: D005290:Ferric Compounds / Q000737:chemistry*; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000737:chemistry*
chemical_list: D005290:Ferric Compounds; D009942:Organometallic Compounds