Four novel compounds, [Cd(tp)(bpp)]_n (1), [Cd(tp)(bpy)]_n (2), [{Cd₄(bpa)₄(bpy)₆}·(bpy)_0.5·7H₂O]_n (3) and [Cd₂{(Htp)(tp)_1.5}(bpe)]_n (4) [tp = terephthalate, bpp = 1,3-bis(4-pyridyl)propane, bpy = 4,4′- bipyridine, bpa = 4,4′-biphenyldicarboxylate, bpe = 1,2-bis(4-pyridyl)ethane], of cadmium(II) polycarboxylate coordination polymers based on mixed ligands were obtained by a hydrothermal method. Complex 1 (C₂₁H₁₈CdN₂O₄) crystallizes in the orthorhombic Pbca space group [a = 11.9401(0) Å, b = 16.8148(3) Å, c = 20.2743(3) Å, and Z = 8]. Complex 2 (C₁₈H₁₂CdN₂O₄) belongs to the monoclinic C2/m space group [a = 20.299(3) Å, b = 10.720(1) Å, c = 11.764(2) Å, β = 110.944(2)°, and Z = 6]. Complex 3 (C₁₂₁H₉₈Cd₄N₁₃O₂₃) belongs to the monoclinic P2₁/c space group [a = 23.2208(0) Å, b = 11.8103(1) Å, c = 45.4670(6) Å, β = 104.516(1)°, and Z = 4]. Complex 4 (C₃₂H₂₃Cd₂N₂O₁₀) belongs to the monoclinic P2₁/n space group [a = 6.9896(1) Å, b = 22.6294(1) Å, c = 19.7738(3)Å, β = 99.380(1)°, and Z = 4].The Cd^II centers in the four compounds are bridged by mixed polycarboxylate ligands with bpy and related species to form the twofold parallel interpenetration topology of an undulating 2D 4⁴ net for 1, a twofold interpenetration topology of a 3D α-Po net for 2, a fourfold interpenetration topology of a 3D 5-connected borazone 4⁶6⁴ net for 3 and an interesting 3D spiral pipe-like structure with a bolt for 4. These four compounds exhibit strong fluorescent emissions at 549 and 582 nm (λ_ex = 532 nm) for 1, 493 nm (λ_ex = 360 nm) for 2, 413 and 424 nm (λ_ex = 315 nm) for 3 and 350 nm (λ_ex = 220 nm) for 4 in the solid state at room temperature. These are novel structural topologies and could be significant in the field of photoactive materials. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)

The first successful attempt to construct 3D supramolecular frameworks with high-nuclear 3d–4f heterometallic clusters as a node is reported. The self-assembly of Ln³⁺, Cu²⁺ and amino acid in solution leads to the formation of two polymers, 35-nuclear complex {Sm₆Cu₂₉} 1 with a primitive cubic net-like structure and 36-nuclear complex {Nd₆Cu₃₀} 2 with a face-centred cubic network type structure. Glycine and L-proline, respectively, were used as ligands. It should be noted that 2 has a chiral framework. X-ray structure analyses show that 1 crystallizes in the triclinic P space group (a=19.6451(8), b=20.4682(8), c=20.7046(8) Å, α=89.453(1), β=66.290(1), γ=68.572(1)°, V=7003.0(5) ų and Z=1) and 2 belongs to the cubic P2(1)3 space group (a=b=c=32.4341(3) Å, V=34 119.7(5) ų and Z=4). Both complexes utilize Ln₆Cu₂₄ octahedral clusters as nodes and trans-Cu(amino acid)₂ groups as bridges. Electrical conductivity measurements reveal that both polymers behave as semiconductors.

[{Co(1,10-phen)₂}₂{(Mo₄O₁₂)(O₃PCH₂CH₂PO₃)}·(H₂O)] (1), [{Co(1,10-phen)₂}₂{(Mo₄O₁₂)(O₃PCH₂CH₂CH₂PO₃)}·(1.5H₂O)] (2) and [{Co(1,10-phen)₂(H₂O)₂}{Co(1,10-phen)₂(H₂O)}{(Mo₅O₁₅)(O₃PCH₂CH₂CH₂CH₂PO₃)}·(6H₂O)] (3) were synthesized by self-assembly of H₂O₃P(CH₂)_nPO₃H₂ (n = 2−4), polyoxomolybdate and [Co(1,10-phen)₂]²⁺ (1,10-phen = 1,10-phenanthroline) under hydrothermal conditions. Compounds 1 and 2 are novel heterometallic hexanuclear clusters, while compound 3 is a new linear polymer. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)

Hydrothermal reactions of Cd^II, Co^II, and Mn^II with the mixed ligands 3,4-pyridinedicarboxylate (pydc), 1,3-bis(4-pyridyl)propane (bpp), or 1,2-bis(4-pyridyl)ethane (bpe) gave crystals of {[Cd(pydc)(bpp)]·0.5H₂O}_n (1), {[Co(pydc)(H₂O)(bpe)_0.5]·0.5H₂O}_n (2), and {[Mn(pydc)(H₂O)(bpe)_0.5]· 0.5H₂O}_n (3), respectively. Single-crystal X-ray analyses reveal that these are all three-dimensional non-interpenetrating coordination polymers. Their structures alter markedly with the conformation and the function of the ligands. In 1, the 3,4-pyridinedicarboxylate acted as a three-connector, a coordination topology of the type (3,5) [containing 3 and 5 connected centers] being generated through self-assembly, while in 2 and 3, with the help of the four-connector 3,4-pyridinedicarboxylate and the terminal ligand water molecule, another three-dimensional framework with a coordination topology of the type (4, 5) was obtained. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)

Two novel coordination polymers formed by cobalt nitrate and 1,2-bis(4-pyridyl)ethane with the homologous ligands 2-aminoterephthalic acid and terephthalic acid, respectively, have been prepared. One displays a fivefold diamond-type feature while the other exhibits a twofold interpenetrating structural motif. The thermal and photoluminescence properties associated with their structures have been characterized and studied. (© Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002)

Five novel heptanuclear trigonal-prismatic polyhedra, Na₄[PrNi₆(Gly)₉(μ₃-OH)₃(H₂O)₆]⋅(ClO₄)₇ (1), Na₂[PrNi₆(Gly)₈(μ₃-OH)₃(μ₂-OH₂)(H₂O)₆]⋅(ClO₄)₆⋅(H₂O)₂ (2), Na[DyNi₆(Gly)₇(μ₃-OH)₃(μ₂-OH₂)₂(H₂O)₆]⋅(ClO₄)₆⋅H₂O (3), [SmNi₆(Gly)₆(μ₃-OH)₃Cl₃(H₂O)₆]⋅Cl₃⋅(H₂O)₉ (4), and [ErNi₆(Gly)₆(μ₃-OH)₃Cl₃(H₂O)₆]⋅Cl₃⋅(H₂O)₉ (5), were synthesized through self-assembly and characterized by X-ray structure analysis. Complex 1 crystallizes in the trigonal P3 space group (a=b=18.1121(2), c=11.987(0) Å, and Z=2). Complex 2 belongs to the triclinic P space group (a=16.0145(3), b=20.58650(10), c=20.8452(3) Å, α=78.0590(10), β=67.9200(10), γ=68.1540(10)°, and Z=4). Complex 3 belongs to the monoclinic P2(1)/m space group (a=14.9863(3), b=13.533, c=15.6171(3) Å, β=116.8970(10)°, and Z=2). Complexes 4 and 5 are isomorphous (4: trigonal, P; a=b=11.8661(4), c=18.2034(10) Å, Z=2; 5: a=b=11.9001(5), c=18.1229(11) Å, Z=2). A Ln³⁺ ion is in the center of the prism formed by six nickel atoms. It coordinates to nine oxygen atoms. Its coordination polyhedron may be best described as a tricapped trigonal prism. The five complexes all have a core of [LnNi₆(Gly)₆(μ₃-OH)₃(H₂O)₆]⁶⁺ and were obtained through the edge-ligand exchange of the three μ₂-OH₂ ligands of [LnNi₆(Gly)₆(μ₃-OH)₃(H₂O)₆(μ₂-OH₂)₃]⁶⁺ partly or wholly by glycine or Cl⁻. Magnetic measurements reveal that 1 and 4 exhibit antiferromagnetic interaction, while 5 exhibits a ferromagnetic interaction.

Wellenförmige, zickzackförmige und helicale Polymere entstehen bei der Reaktion von [MoS₄]²⁻, Ag₂S und einem Gegenkation. Die Struktur des polymeren Anions hängt dabei von der Ladung des Kations ab: Mit einem zweifach geladenen Kation entsteht z. B. eine schmetterlingsartige Anionenkette (siehe Bild). Eine höhere Ladungszahl des Kations führt hierbei tendenziell zu einer kompakteren Kettenstruktur.

Wavelike, zigzag, and helical polymers are formed by the reaction of [MoS₄]²⁻, Ag₂S, and a complementary cation. The framework of the polymeric anions depends on the valence state of the latter. For example, the butterfly-type anionic chain shown in the picture is formed upon use of a divalent cation. There is a general tendency that a higher valence state of the cation will induce a more compact chain structure.