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A zinc-based one-dimensional (1D) coordination polymer ([Zn(H2mpca)2(tfbdc)(H2O)], Zn-ODCP) has been synthesized and characterized by spectroscopic and physicochemical methods, single-crystal X-ray diffraction, and thermogravimetric analysis (H2mpca = 3-methyl-1H-pyrazole-4-carboxylic acid; H2tfbdc = 2,3,5,6-tetrafluoroterephthalic acid). Zn-ODCP shows blue luminescence in the solid state. When Zn-ODCP acts as an anode material for lithium ion batteries, it exhibits a good cyclic stability and a higher reversible capacity of 300 mAh g–1 at 50 mA g–1 after 50 cycles. The higher capacity may be mainly ascribed to the metal ion and ligand all taking part in lithium storage. Searching for electrode materials of lithium ion batteries from 1D metal coordination polymers is a new route.

The reactions of manganese(II) acetate or perchlorate, sodium azide, and the inner-salt-type dicarboxylate ligand 1,3-bis(4-carboxylato-1-pyridinium)propane (L) under different conditions yielded four different Mn(II) coordination polymers with mixed azide and carboxylate bridges: {[Mn(L)(N(3))]ClO(4).0.5H(2)O}(n) (1), {[Mn(2)(L)(2)(N(3))(2)][Mn(N(3))(4)(H(2)O)(2)].2H(2)O}(n) (2), {[Mn(2)(L)(2)(N(3))(2)(H(2)O)(2)]Br(N(3)).2H(2)O}(n) (3), and [Mn(4) (L)(2)(N(3))(8)](n) (4). The compounds exhibit great diversity in their structures and magnetic properties. Both 1 and 2 contain anionic chains featuring a mixed (OCO)(2)(EO-N(3)) triple bridge (EO = end-on) between adjacent Mn(II) ions. In 1, two independent sets of triple bridges with apparently different structural parameters alternate in the AABB sequence, and the resulting alternating chains are cross-linked into a cationic 3D framework by the cationic dipyridinium spacers. Differently, the chains in 2 have uniform bridges and are interlinked into a 2D coordination layer. An expression of the magnetic susceptibility for 1D systems with alternating J(1)J(1)J(2)J(2) interactions has been deduced and applied to 1. Magnetic studies on 1 and 2 reveal that the (OCO)(2)(EO-N(3)) triple bridges induce antiferromagnetic coupling between Mn(II) ions, and magnetostructural analyses suggest that the magnitude of the coupling can be correlated to the Mn-N and Mn-N-Mn parameters. Compound 3 contains 2D coordination layers in which the chains with alternating double EO-azide and double carboxylate bridges are interlinked by the dipyridinium spacers, and magnetic studies suggest alternating ferro- and antiferromagnetic interactions through the alternating bridges. The 3D framework of compound 4 is formed by the organic ligands interlinking the unique manganese-azide-carboxylate layers in which the [Mn(4)(mu(3)-N(3))(2)(mu(2)-N(3))(2)(mu(2)-COO)(4)] clusters are interlinked through EE-azide bridges (EE = end-to-end). The structure represents a novel type of self-catenated 8-connected 3D net. Magnetostructural analyses suggest that all of the short bridging moieties in 4, including (mu(3)-EO-N(3))(2), (OCO)(EO-N(3)), (OCO)(EO-N(3))(2), and single EE-N(3), propagate antiferromagnetic coupling.

Assembly of a family of monomeric, dimeric, and polymeric W/Cu/S clusters from a precursor cluster [Et(4)N][Tp*W(mu(3)-S)(3)(CuBr)(3)] (Tp* = hydridotris(3,5-dimethylpyrazol-1-yl)borate) (1) and various N-donor ligands was reported. The treatment of 1 with pyridine (py) or aniline (ani) in the presence of NH(4)PF(6) afforded a cationic cluster [Tp*W(mu(3)-S)(3)Cu(3)(py)(3)(mu(3)-Br)](PF(6)) (2) and a neutral cluster [{Tp*W(mu(3)-S)(3)(CuBr)(3)}(mu(6)-Br){Tp*W(mu(3)-S)(3)Cu(3)(ani)(3)}] x 4 ani x 0.5 Et(2)O (3 x 4 ani x 0.5 Et(2)O). On the other hand, the treatment of 1 with excess 4,4'-bipyridine (4,4'-bipy) or 1,2-bis(4-pyridyl)ethylene (bpee) followed by the addition of NH(4)PF(6) led to the formation of a polymeric cluster {[Tp*W(mu(3)-S)(3)Cu(3)(4,4'-bipy)(3)(mu(3)-Br)](PF(6)) x H(2)O}(n) (4) and a neutral cluster [{Tp*W(mu(3)-S)(3)Cu(3)Br(2)}(2)(bpee)] x 0.5 CH(2)Cl(2) (5 x 0.5 CH(2)Cl(2)). Meanwhile, analogous reactions of 1 with excess 1,2-bis(4-pyridyl)ethane (bpe) or 1,3-bis(4-pyridyl)propane (bpp) in DMF under the presence of NH(4)PF(6) resulted in the formation of two polymeric clusters {[{Tp*W(mu(3)-S)(3)Cu(3)(mu(3)-Br)}(2)(bpe)(3)](PF(6))(2) x MeCN}(n) (6) and {[Tp*W(mu(3)-S)(3)Cu(3)Br(mu(3)-Br)(bpp)] x DMF}(n) (7). Compounds 1-7 were characterized by elemental analysis, IR spectra, UV-vis spectra, (1)H NMR, electrospray ionization mass spectra, and X-ray crystallography. The anion of 1 has an incomplete cubanelike [Tp*W(mu(3)-S)(3)(CuBr)(3)] structure, while the cation of 2 has a cubanelike [Tp*W(mu(3)-S)(3)Cu(3)(mu(3)-Br)] structure. Compound 3 may be viewed as having a corner-shared double cubanelike structure that consists of one [Tp*W(mu(3)-S)(3)Cu(3)(ani)(3)](2+) dication and one [Tp*W(mu(3)-S)(3)(CuBr)(3)](-) anion linked by a mu(6)-Br bridge. For 4, each [Tp*W(mu(3)-S)(3)Cu(3)(mu(3)-Br)] unit works as a pyramidal three-connecting node to connect its equivalent ones via three 4,4'-bipy bridges to yield a 2D (6,3) cationic network. Compound 5 has a dimeric structure in which two incomplete cubanelike [Tp*W(mu(3)-S)(3)Cu(3)Br(2)] cores are bridged with one bpee ligand. For 6, each dimeric [{Tp*W(mu(3)-S)(3)Cu(3)(mu(3)-Br)}(2)(bpe)(2)] unit is interconnected via a pair of bpe bridges to form a 1D zigzag cationic chain. Compound 7 has a 1D spiral chain in which each [Tp*W(mu(3)-S)(3)Cu(3)Br(mu(3)-Br)] core is interlinked by a couple of bpp bridges. The formation of 2-7 from the precursor cluster 1 through various N-donor ligands offers a new way to the design and assembly of the W/Cu/S clusters with interesting molecular and supramolecular arrays.

Four new inorganic-organic hybrid coordination polymers in which 1D or 2D manganese(II) azido inorganic motifs are interlinked into higher-dimensional networks have been synthesized by use of a series of bis(pyridyl)-type organic bridging ligands (linkers) with different side groups and/or different coordination orientations. The dimensionality and the topology of the manganese(II) azido motif and the whole structure are sensitive to the organic linkers used. Compounds 1 and 3 are 3D coordination polymers with pillared-layer architectures: in 1, 2D Mn(II) layers with alternate double end-on (EO) and single end-to-end (EE) azido bridges are pillared by zigzag organic linkers, and 3 is built from single EE azido-bridged Mn(II) layers and linear organic linkers. The 3D nets of 1, 3, and related compounds have been related to the specific length and coordination orientation of the organic pillars and the undulate shape of the manganese(II) azido layers. Consistent with their structures, both 1 and 3 exhibit weak ferromagnetism due to spin canting. Compound 1 is a weak ferromagnet with T(c) = 16 K, and 3 is a metamagnet with T(c) = 23 K. On the other hand, compounds 2 and 4 are 2D coordination networks in which 1D manganese(II) azido chains are interlinked by organic linkers: 2 is the first 2D network built from Mn(II) chains with alternate double EE and double EO azido bridges, which mediate antiferro- and ferromagnetic interactions, respectively; 4 is the first 2D network built from Mn(II) chains with only single EE azido bridges, which mediate antiferromagnetic interactions. The magnetic susceptibility of 4 exhibits a rapid rise at very low temperature, which may be attributed to paramagnetic impurities or spin canting.

The reaction of [(TMS)2N]3La(mu-Cl)Li(THF)3 (1) and HSPh produced a bimetallic complex [{(TMS)2N}2La(THF)]2(mu-SPh)(mu-Cl)] (2). Compound [{(TMS)2N}2La5O(SPh)10LiCl2(THF)6] (3) was prepared by control of the hydrolysis of 2 and LiCl or 1 and HSPh with the proper amount of water. 1 was treated first with 1/6 equiv of H2O and then with equimolar HSPh; a polymeric complex [{(TMS)2N}2(mu-SPh)La(mu-SPh)Li(THF)2](infinity) (4) was isolated. 3 contains a central [(mu-SPh)4(mu3-SPh)2{La(THF)}4(mu3-O)]4+ tetrahedral fragment in which two La atoms are linked by a pair of mu-SPh- and mu3-Cl- ligands to a [{(TMS)2N}2La]+ fragment, while the other two are bridged by two mu-SPh- ligands to a [Li(THF)2]+ fragment, forming a bee-shaped structure.

Manganese-based layered coordination polymer ([Mn(tfbdc)(4,4′-bpy) (H2O)2], Mn-LCP) with microporous structure was synthesized by reaction of 2,3,5,6-tetrafluoroterephthalatic acid(H 2tfbdc) and 4,4′-bipyridine(4,4′-bpy) with manganese(II) acetate tetrahydrate in water solution. Mn-LCP was characterized by elemental analysis, IR spectra, thermogravimetric analysis, X-ray single-crystal structure analysis, and powder X-ray diffraction. Magnetic susceptibility data from 300 to 1.8K show that there is a weak antiferromagnetic exchange between Mn(II) ions in Mn-LCP. As anode material, the Mn-LCP electrode exhibits an irreversible high capacity in the first discharge process and a reversible lithium storage capacity of up to about 390 mA h/g from the fourth cycle. It might provide a new method for finding new electrode materials in lithium-ion batteries © 2013 American Chemical Society.

Three isomorphous metal-organic frameworks of formula [M(ppdc)(H(2)O)(2)](n) [M = Mn(II), Fe(II), and Co(II)] were synthesized from sodium p-phenylenediacrylic (Na(2)ppdc). Crystallographic studies revealed that the compounds are layer-pillared 3D frameworks in which the square-grid M(II) layers with single carboxylate bridges are interlinked by long organic spacers with large interlayer separations of about 13 Å. Magnetic investigations indicated that they all display intralayer antiferromagnetic interactions through the carboxylate bridges in the unusual skew-skew coordination mode but the bulk behaviors are quite different. The Co(II) compound, like most compounds containing similar M-O-C-O-M layers, shows no 3D magnetic ordering down to 2 K, while the Mn(II) and Fe(II) compounds exhibit spin-canted ordering, behaving as a weak ferromagnet (T(C) = 3.8 K) and a metamagnet (T(N) = 3.8 K, H(c) = 650 Oe), respectively. Spin-canted ordering is still a rarity in this series of materials. Magnetostructural comparisons with analogous compounds indicate that the occurrence of spin-canted ordering can be related to the uncommon skew-skew and anti-anti coordination modes of carboxylate bridges, which induce stronger antiferromagnetic interactions than the common syn-anti mode.

A series of transition metal coordination polymers with azide and flexible zwitterionic dicarboxylate ligands was synthesized and structurally and magnetically characterized. These compounds are formulated as [M(2)(L(1))(N(3))(4)] (L(1) = 4,4'-trimethylenedipyridinio-N,N'-diacetate and M = Mn, 1; Co, 2; and Ni, 3) and [ML(2)(N(3))(6)(H(2)O)(2)] (L(2) = 4,4'-dipyridinio-N,N'-diacetate and M = Mn, 4; Co, 5). The isomorphous compounds 1-3 consist of two-dimensional coordination layers in which the anionic uniform chains with mixed triple bridges (two end-on (EO) azides and a syn-syn carboxylate) are cross-linked by the flexible cationic 4,4'-trimethylenedipyridinium spacers, while the isomorphous compounds 4 and 5 consist of alternating chains with triple (two EO azides plus a carboxylate) and double (two end-to-end azides) bridges, the 4,4'-dipyridinium spacers serving as side bridges along the chain. Magnetic studies demonstrated that the triple bridge transmits antiferromagnetic coupling in the Mn(II) compounds (1 and 4) but ferromagnetic coupling in the Co(II) and Ni(II) species (2, 3, and 5). The differences have been discussed in terms of the collaboration or competition between the carboxylate and azide pathways. Compound 4 exhibits alternating antiferromagnetic interactions, while alternating ferromagnetic-ferromagnetic-antiferromagnetic interactions with spin canting are suggested for 5.

The coordination of pyridazine-3,6-dicarboxylate by manganese(II) leads to unusual anionic binuclear trigonal prisms, which coassemble with the hexaaquamanganese(II) antiprisms to generate a hydrogen-bonded CsCl-type three-dimensional network.

A novel 3D assembly of molecular cobalt cubes, where the mixed-valence cubes are linked by macrocyclic nickel(II) complexes through coordination and hydrogen bonds, has been constructed by the metalloligand strategy.