title: Synthesis, structure and magnetism of homologous series of polycrystalline cobalt alkane mono- and dicarboxylate soaps.
abstract: Carboxylate-bridged chain complexes of Co(II) (the diaquacobalt(II) mono- and ,-dialkanoates) form two homologous series of layered compounds which have been fully characterised both structurally and magnetically. The crystal structures of two selected members, [Co[CH3(CH2)10COO]2(H2O)2] and [Co[CH3(CH2)18COO]2(H2O)2], have been solved by X-ray powder diffraction and selected-area electron diffraction methods, and refined by the Rietveld technique. Crystal data: monoclinic, P 2(1)/a; a=9.688(1), b=7.5495(9), c=37.281(5) A, =96.70(3) primary, Z=4; and monoclinic, P 2(1)/a; a=9.7260(7), b=7.5477(7), c=57.53(1) A, =94.66(4) primary, Z=4, respectively. Their isomorphous structures contain layers of octahedral diaquacobalt(II) ions bonded to two chemically inequivalent alkanoates, one chelating and one bridging two Co atoms about 6.3 A apart, thus confirming the rare anti-anti conformation mode of the -RCOO groups recently proposed for diaquacobalt(II) ,-dodecanedioate. Extensive magnetic characterisation allowed estimation of the feeble antiferromagnetic coupling, which is weaker in the mono- than in the dialkanoate series.
authors: Institut de Physique et Chimie des Matériaux de Strasbourg, UMR 7504 CNRS-ULP-ECPM, France.
authors: Jean-Micel
authors: JM
authors: Rueff
authors: Norberto
authors: N
authors: Masciocchi
authors: Pierre
authors: P
authors: Rabu
authors: Angelo
authors: A
authors: Sironi
authors: Antoine
authors: A
authors: Skoulios