Heterometallic one-dimensional arrays containing cyanide-bridged lanthanide(III) and transition metals

One-dimensional arrays having the general formula {(DMF)(10)Ln(2)[M(CN)(4)](3)}(infinity) [Ln = Sm, Eu, Er, Yb and M = Ni, Pd, Pt] were prepared from the reactions of 2:3 molar ratios of LnCl(3) with K-2[M(CN)(4)] in DMF (DMF = N,N-dimethylformamide). Under similar conditions using 1:1 molar ratios of SmCl3 and K-2[Ni(CN)(4)] in DMF or YbCl3 add K-2[Ni(CN)(4)] in DMA (DMA = N,N-dimethylacetamide), the one-dimensional arrays {(DMF)(5)Sm-[Ni(CN)(4)]Cl}(infinity), 8, and {(DMA)(4)Yb[Ni(CN)(4)]Cl}(infinity), 9- were prepared. An earlier study of {(DMF)(10)Yb[Ni(CN)(4)](3)}(infinity), 3, and {(DMF)(10)Yb-2[Pt(CN)(4)](3)}(infinity), 7, showed that two different yet related one-dimensional arrays can be adopted. In the present study. X-ray crystal structures of {(DMF)(10)Sm-2[Ni(CN)(4)](3)}(infinity), 1, and {(DMF)(10)Er-2[Ni(CN)(4)](3)}(infinity), 2, are shown to be isomorphous with {(DMF)(10)Yb-2[Ni(CN)(4)](3)}(infinity), 3, while {(DMF)(10)Sm-2[Pd(CN)(4)](3)}(infinity), 4, {(DMF)(10)-Eu-2[Pd(CN)(4)](3)}(infinity), 5, and {(DMF)(10)Yb-2[Pd(CN)(4)](3)}(infinity), 6, an isomorphous with {(DMF)(10)Yb-2[Pt(CN)(4)](3)}(infinity), 7. Single-crystal X-ray crystal structure determinations reveal that arrays 1, 2, and 3 consist of cyanide-bridged "diamond"-shaped Ln(2)Ni(2) metal cores. These metal forts are linked together in an infinite array through cyanide bridges by [Ni(CN)(4)](2-) anions generating a single-strand chain. Crystal data for I: triclinic space group P (1) over bar, a = 10.442(5) Angstrom, b = 10.923(2) Angstrom, c = 15.166(3) Angstrom. alpha = 74.02(2)degrees, beta = 83.81(3)degrees, gamma = 82.91(2)degrees, Z = 2. Crystal data for 2: triclinic space group P (1) over bar. a = 10.172(1) Angstrom, b = 11.111(3) Angstrom, c = 15.369(2) Angstrom, alpha = 73.17(2)degrees, beta = 85.15(1)degrees, gamma = 83.38(2)degrees, Z = 2. Arrays 4, 5, 6, and 7 consist of two parallel zigzag chains that are linked together through bridging [M(CN)(4)](2-) anions. Crystal data for 4: triclinic space group P (1) over bar, n = 9.304(2) Angstrom, b = 11.351(3) Angstrom, c = 16.257(5) Angstrom, alpha = 81.62(2)degrees, beta = 77.51(2)degrees, gamma = 82.47(2)degrees, Z = 2. Crystal data for 5: triclinic space group P (1) over bar, a = 9.300(3) Angstrom, b = 11.353(4) Angstrom, c = 16.279(3) Angstrom, alpha = 81.58(2)degrees, beta = 77.37(2)degrees, gamma = 81.58(2)degrees, Z = 2. Crystal data for 6. triclinic space group P (1) over bar, a = 9.164(2) Angstrom, b = 11.718(3) Angstrom, c = 16.122(3) Angstrom, alpha = 79.88(2)degrees, beta = 74.43(2)degrees, gamma = 80.50(2)degrees, Z = 2. Electrical conductance, NMR, and infrared studies of DMF solutions of 1-7 reveal that these arrays are partially ionized in solution. Single-crystal X-ray analyses of the one-dimensional arrays 8 and 9 show that these complexes adopt the commonly observed zigzag chain structure. Crystal data for 8: monoclinic splice group P2(1)/n. a = 7.783(2) Angstrom, b = 17.748(8) Angstrom, c = 21.236(5) Angstrom, beta = 92.87(2)degrees, Z= 4. Crystal data for 9: monoclinic space group P2(1)/n, a = 10.022(2) Angstrom, b = 19.505(4) Angstrom, c = 15.742(3) Angstrom, beta = 105.94(2)degrees, Z = 4. Studies of 8 and 9 in DMF and DMA, respectively, indicate that 8 is partially ionized and 9 is almost completely ionized.