| Polynuclear clusters continue to attract significant interest because of their intriguing geometrical characteristics and fascinating magnetic properties.In this thesis,the reactions of metal salts with acenaphthenequinone monooxime(HL1)and acenaphthenequinone dioxime(H2L2)gave fifteen polynuclear cluster compounds including eight monooxime clusters,five dioxime clusters and two clusters bearing the above-mentioned two oximes.They were characterized by elemental analysis,IR,powder X-ray diffractional analysis and single crystal X-ray diffraction analysis.Their structures and magnetic properties were also investigated systematically.The main work is presented below:1.[Cu3(L1)2(CH3O)2(ClO4)2(Im)2](1),[Cu4(L1)4(CH3O)2(OAc)2]·2H2O(2),[Cu6(L1)4(L2)2(CH3O)2(CH3OH)2(H2O)](ClO4)2·2CH3OH(3) and [Cu?5Cu?2(L1)8(ClO4)2(CH3O)2-(CH3OH)2](4)were separated from the reactions of acenaphthenequinone monooxime(HL1)and acenaphthenequinone dioxime(H2L2)with Cu(ClO4)2·6H2O and Cu(OAc)2·H2O,respectively.The three Cu(?)ions in 1 are bridged to form a linear trinuclear skeleton.The two monooxime ligands in 1 display ?3:?2 bridging mode,and all non-hydrogen atoms of the oxime ligands are in the same plane with the metal ions.The four Cu(?)ions in 2 are consolidated in turn by four monooxime ligands,and further linked by acetate and methoxide ligands alternately,forming a planar quadrilateral tetranuclear skeleton.Complex 3 is a hexanuclear cluster bearing the two oxime ligands.The monooxime and dioxime ligands,which display ?3:?2,?5:?4 and ?5:?4 bridging modes,respectively,linked the two ?3-OH--centred Cu3 triangles into a hexanuclear cluster with dihedral angle of 85.576° between the two triangular planes.Complex 4 is a heptanuclear complex with five four/five/six-coordininated Cu(?)atoms and two two-coordininated Cu(I)atoms.The seven Cu atoms are linked into a vertex-sharing bitetranedral skeleton by the monooxime ligands which display two bridging modes of ?3:?2 and ?4:?3.2.[Ni2(L1)2(py)6](ClO4)2·CH3OH(5),[Ni8(O2)(L1)4(N3)8(OAc)2(DMF)2-(CH3CN)(CH3OH)][Ni8(O2)(L1)4(N3)8(OAc)2(DMF)4]·5CH3OH·2H2O(6),[Ni8(OH)4(L1)8-(HCO3)2(Mep)(MepH)2]2(SO4)·10H2O·2CH3CH2OH(7) and [Ni12(OH)4(L1)8(L2)4(H2O)8](CO3)2(8)were separated from the reactions of acenaphthenequinone monooxime(HL1)and acenaphthenequinone dioxime(H2L2)with Ni(ClO4)2·6H2O and NiSO4·7H2O,respectively.Complex 5 is a dinuclear complex.Complex 6 is a Ni8 cluster.The O22- in 6 links six Ni(?)ions to form a D3d-symmtric Ni6 unit,which is further connected to another two Ni(?)ions by six ?3-N3-ions,leading to the formation of the Ni8 skeleton of 6.Complex 7 is a planar octanuclear Ni(?)cluster.Its skeleton is formed by the connection a nickel ion through two HCO3- ions to a Ni7(?3-OH)4 core which consists of four ?3-OH- centred Ni(?)triangles sharing one Ni(?)vertex.Complex 8 is a Ni12 cluster with mixed oxime ligands.The monooxime and dioxime ligands connect twelve Ni(?)ions to form a Ni12 cluster with all Ni(?)ions nearly in one plane.The magnetic studies of complexes 5 and 6 revealed the presence of dominant antiferromagnetic interactions between the metal ions in both 5 and 6.3.The reactions of acenaphthenequinone monooxime(HL1)with Co(OAc)2·4H2O,Co(ClO4)2·6H2O,respectively,gave two complexs[Co(L1)2(MepH)](9) and[Co2(L1)2(py)6](ClO4)2·2H2O(10).Complex 9 was a mononuclear Co(?)complex.Complex 10 is isomorphous to complex 5.[Co2(L2)2(HL2)(py)3]ClO4(11)and[Co?2Co?(L2)3(py)6]ClO4(12)were separated from the reactions of acenaphthenequinone dioxime(H2L2)with Co(ClO4)2·6H2O,respectively.The Co ions in 11 and 12 are bridged to form a dinuclear and a linear trinuclear complex with their Co ions six-coordinated.The magnetic investigation of complexes 10 and 11 revealed the presence of dominant antiferromagnetic interactions between the metal ions in both 10 and 11.4.[Mn3(?3-O)(L2)3(OAc)(DMF)2](13),[Mn3(?3-O)(L2)3(OAc)(py)3](14),[Mn6(?3-O)2(L2)6(H2O)(py)7](ClO4)2·py·2CH3OH·H2O(15)were separated from the reactions of acenaphthenequinone dioxime(H2L2)with Mn(ClO4)2·6H2O and Mn(OAc)2·4H2O,respectively.Complex 13 and 14 are approximately planar trinuclear manganese clusters.Their metallic skeleton can be described as a ?3-O2- centred Mn?3 triangle.Complexes 15 preseIts a[Mn6(?3-O)2(L2)6]12+ core which are formed by two Mn?3 triangles via the intertrinuclear mutual coordination.The magnetic properties of complexes 14 and 15 were investigated.It reveals the presence of dominant antiferromagnetic interactions between the metal ions in both 14 and 15. |
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