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Structure and magnetism of a Mn(III)-Mn(II)-Mn(II)-Mn(III) chain complex
Róbert Uhrecký1, Ján Moncoľ, Marian Koman
1Institute of Inorganic Chemistry, FCHPT, Slovak University of Technology, Bratislava 812 37, Slovakia. robert.uhrecky@stuba.sk
Abstract:
A novel tetranuclear manganese(II/III) complex with anions of pyridine-2,6-dicarboxylic acid (dipicolinic acid) has been synthesised and magneto-structurally characterised. The crystal structure of [Mn(II)2Mn(III)2(dipic)6(H2O)4]·2CH3OH·4H2O has been determined by single-crystal X-ray diffraction. The tetranuclear complex molecule [Mn(II)2Mn(III)2(dipic)6(H2O)4] is centrosymmetric and two manganese(II) and two manganese(III) atoms are bridged by four dipicolinate ligands. The complex molecules and uncoordinated water and methanol molecules are connected through hydrogen bonds and they form a 3D supramolecular hydrogen-bonding network.
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