| In the past few years, mixed-valent diruthenium systems Ru2Ⅱ,Ⅲ, which bear a high-spin S=3/2ground state with large zero-field splitting, have attracted special attention in the construction of supramolecular magnetic materials. The D4h symmetry Ru2(CO3)43-is an intriguing building blocks for the design and synthesis of molecule-based magnets. Several recently reported works indicate that the carbonate group, CO32-, is an efficient ligand bridge mediating ferromagnetic coupling interaction between spin carriers. In this paper, we report that the simultaneous assembly of Ru2(CO3)43-and metal ions (M=Mg, Mn, Co, Ni, Cu, Zn, Cd) in anaqueous solution leading to the different topology structures may be manipulated by the introduction of different templates, reactants ratio and/or temperature conditions. The syntheses, structures and magnetic properties of these complexes are characterized.The contents include three parts as follows:1Two ionic crystals, namely K(H2O)6[Co(H2O)6]4[Ru2(CO3)4]3·6H2O(1) and K(H2O)6-[Ni(H2O)6]4[Ru2(CO3)4]3·6H2O(2), have been synthesized in aqueous solution under temperature conditions.Both of them contain mixed-valent paddlewheel cores of Ru2Ⅱ,Ⅲ-(CO3)42-,M(H2O)62+(M=Co, Ni) and lattice water, in which antiferromagnetic interaction are observed, the susceptibility data were fitted by different theoretical equations, leading to parameters:compound1:gRu=2.17, gCo=2.47, D=82.7cm-1,θ=-6.29cm-1; compound2: gRu=2.19, gCo=2.10, D=93.1cm-1,θ=-0.52cm-12A series of dimetal tetracarbonates for2-D structure namely CuH[Ru2(CO3)4(H2O)2]·-5H2O(3), ZnH[Ru2(CO3)4(H2O)2]·5H2O(4), KM(H2O)5[Ru2(CO3)4]·5H2O(5)(M=Mg,Mn)(5,6),[{Co(H2O)4}2Ru2(CO3)4(H2O)Cl]·7.5H2O(7) and [{Co(H2O)4}2Ru2(CO3)4(H2O)Cl]·-7.5H2O (8) has been synthesized in aqueous solution under room temperature conditions. All of them contain mixed-valent paddlewheel cores of Ru2(CO3)42-. Complexes3-4show the same structures, in which Ru2and Cu2+ions are connected by μ-CO32-, forming mixed metal layer CuHRu2(CO3)4(H2O)2]n. For compounds5-7, Ru2is conntected by μ-CO32-, forming2-D layer [M(H2O)5Ru2(CO3)4]nn-; In the compound8,[Ru2(CO3)4(H2O)Cl]4-units and Co2+are connected alternatively in a ratio of1:2forming2-D layer{Co(H20)4}2Ru2(CO3)4-(H2O)Cl]n.,Compounds3-4show weak antiferromagnetic interactions. Ferromagnetic interactions are observed in the compounds5-7, the susceptibility data were fitted by different theoretical equations, leading to parameters:Compound3:gRu=2.23, D=119cm-1,θ=-4.13cm-1; Compound4:g=2.15,θ=-0.74cm-1, D=86.0cm-1。 Compound5:gRu=2.19, D=53.6cm-1,θ=5.99cm-1; Compound6:gRu=2.27, gCo=2.47, D=85.9cm-1,8=6.16cm-1R=1.3×10-3; Compound8:gRu=2.22, gCo=2.63, D=72.3cm-1,∪=4.16cm-1, R=1.7×10-3.3Four3D structure diruthenium tetracarbonates were constructed from building block of Ru2(CO3)42-with transitional metal ions Mn2+, Co2+and Cd2+, namely a-K{Cd(H2O)3[Ru2(CO3)4]·5H2O(9),b-KCd(H2O)3[Ru2(CO3)4]·5H2O(10),K[Co(H2O)4Ru2(CO3)4]n·nH2O(11),{Mn4(H2O)16H[Ru2(CO3)4]2[Ru2(CO3)4(H2O)2]}n·11nH2O(12).Complexes9and10are two structure isomers,in which mixed-valent paddlewheel cores of Ru2(CO3)42-are joined by O forming two different layers [Ru2(CO3)4]n3-,and Cd2+ions connected adjacent Ru2(CO3)42-with cis-for9and trans-for10mode forming3-D network,respectively. For complexes11and12, Co2+or Mn2+connected adjacent Ru2(CO3)42-units in different modes forming three dimension networks. Considering the large zero-field splitting of Ru2Ⅱ,Ⅲ and the magnetic interaction between spin carriers, the susceptibility data were fitted by theoretical equations, eading to parameters:compound9:g=2.27,θ=0.34cm-1, D=85cm-1; Compound11: gRu=2.20, gco=2.64, D=85.8cm-1,θ=4.74cm-1, R=1.5×10-3; Compound12:gRu=2.21, D=58.2cm-1,θ=4.25cm-1... |
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