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In this paper, two cadmium(II) coordination polymers [Cd(sdb)(bib)] n ( 1) and {[Cd2(pda)2(bib)2] ·0.5H2O} n ( 2) [H2sdb = 4,4′-sulfonyl-dicarboxylic acid, H2pda = 1,3-phenylenediacetic acid, and bib = 1,4-bis(1-imidazolyl) benzene] were synthesized and characterized by hydrothermal methods. Complex 1 displays a 3,5-connected topological net and complex 2 shows a 4-connected non-interpenetrated pcu framework. Furthermore, the luminescent properties for complexes 1 and 2 were investigated. [ABSTRACT FROM AUTHOR]

A newly synthesized coordination polymer, [Cd(DMSO)(H2O)]3[Fe(CN)6]2 (CdHCF‐T), based on Cd2+ and Fe(CN)63− ions was prepared in a DMSO/H2O mixed solution and crystalized in the trigonal space group P‐31c. This novel 3D structure presented an interesting single‐crystal to single‐crystal transformation when the coordinated DMSO molecules were replaced by H2O, forming a well‐known Cd Prussian Blue analogue (Cd‐PBA). This occurrence is a rare phenomenon in transition metal hexacyanometallates and may provide a new strategy for obtaining new structures and overcoming the difficulty of growing single crystals of Prussian Blue analogues. Subsequent gas sorption and separation investigations based on the obtained Cd‐PBA were also carried out to evaluate its C2H2/CO2 separation capability. [ABSTRACT FROM AUTHOR]

A new binuclear complex {[Cd(phen)2(H2O)] ⋅ (TMA)2−}2 has been synthesized through the reaction of o‐phenanthroline (phen), 3‐thiophenemalonic acid (H2TMA), and cadmium acetate in a 1 : 2 (v/v) EtOH‐H2O mixture at room temperature. This complex can undergo single‐crystal‐to‐single‐crystal (SCSC) transformation to a new mononuclear complex [Cd(phen)3] ⋅ 2(HTMA)− ⋅ H2TMA} by a simple in‐situ solvent evaporation method at room temperature without changing the reaction system. In the whole SCSC process, with the solvent water molecules decreasing and the concentration of ligands increasing, the phen ligands replace the coordination water and coordinate with cadmium ions, finally resulting in the crystal structure transformation in the solid state. [ABSTRACT FROM AUTHOR]

Two new fluorescent coordination polymers based on pamoic acid and different polydentate N‐donor ligands, namely {[Cd(PA)(TPTZ)(H2O)](DMF)2}n (1) and [Cd(PA)(BIB)]n (2) [H2PA = pamoic acid, TPTZ = 2,4,6‐tri(2‐pyridyl)‐1,3,5‐triazine, BIB = 1,4‐bis(1‐imidazolyl)benzene], were synthesized and characterized. Complex 1 showed a 1D zigzag chain structure with intramolecular hydrogen bonds. The 2D supramolecular structure in 1 was formed through π–π stacking interactions and intermolecular hydrogen bonds. Complex 2 displayed a 2D network structure. Intramolecular hydrogen bonds and π–π stacking interactions were observed in 2. By studying the fluorescence sensing performance of two coordination polymers, complex 1 exhibited high selectivity for tracking Al3+ ion and complex 2 could discriminately detect inorganic or aliphatic amines with high selectivity. [ABSTRACT FROM AUTHOR]

Two isostructural CdII frameworks, [Cd2(MMA)2(bpy)(H2O)2]n (1) and [Cd2(MMA)2(bpe)(H2O)2]n (2), were synthesized solvothermally with hybrid flexible methylmalonic acid (H2MMA) and rigid 4,4'‐bipyridine (bpy) or trans‐1,2‐bis(4‐pyridyl)ethylene (bpe) as coligands. Single‐crystal X‐ray diffraction analyses reveal that complexes 1 and 2 display a three‐dimensional (3D) framework structure composed of 2D [Cd(MMA)] layer unit and bpy/bpe linker, and exhibit a (3,4)‐connected topological network with Schläfli symbol of {63}{65.8}. The solid‐state luminescent properties were studied, and 1 and 2 show a distinct emission centered at 465 and 531 nm, respectively. [ABSTRACT FROM AUTHOR]

Under the solvo‐thermal conditions, two novel CdII mixed‐ligand coordination materials with 2,6‐(1,2,4‐triazole‐4‐yl)pyridine(L1) and aromatic poly‐carboxylic acid co‐ligands such as 5‐R‐isophthalic acid (R = nitro, sulfo), namely [Cd(L1)(NO2‐BDC)(H2O)2]·2H2O (1) and [Cd(L1)(HSIP)(H2O)]·4H2O (2) (NO2‐H2BDC = 5‐nitroisophthalic acid, H3SIP = 5‐sulfobenzene ‐isophthalic acid) were successfully prepared. These CdII mixed‐ligand coordination polymers 1–2 have been measured by crystal X‐ray analysis, FT‐IR spectra and powder X‐ray diffraction analyses. In 1, these seven‐coordinate CdII atoms (Cd1) are inter‐linked by didentate 5‐nitroisophthalic acid ligands forming 1D chain structures. In 2, these L1 and partially de‐pronated HSIP2– are inter‐linked by central CdII centers and are arranged into the unique 2D micro‐porous metal‐organic framework of 2. Side view of 2, it is noted that numerous oxygen atoms of un‐coordinated carboxylate groups and coordinated SO3 groups protrude out and decorate the 2D framework of 2. PXRD patterns of 1 and 2 sample is tested, which is consistent with the simulated PXRD diffraction pattern. Photoluminescence studies show that 2 is highly selective and sensitive to trace elements of Eu3+ with excellent Ksv value (7.86 × 104m–1) and low detection limit (5.56 × 10–2 mM), which also provides a convenient method and platform for real‐time detection of Eu3+. [ABSTRACT FROM AUTHOR]

A new coordination polymer (CP), namely, [Cd(HL)(4,4′‐bipy)] (1) (H3L = 4‐(5‐carboxy‐pyridine‐3‐yloxy)‐phthalic acid, 4,4′‐bipy = 4,4′‐bipyridine), was synthesized employing a V‐shaped asymmetric tricarboxylic acid ligand under hydrothermal condition. Single‐crystal X‐ray diffraction analysis indicates that compound 1 exhibits a novel three‐dimensional (3D) framework with (3, 5)‐connected (63)(69·8) topology. Meanwhile, it shows high selectivity and sensitivity for oxoanion pollutants CrO42–, Cr2O72–, and MnO4– anions in aqueous solutions with detection limits of 4.12 × 10–6 M, 1.75 × 10–6 M, and 6.47 × 10–7 M, respectively. The high selectivity and low detection limit indicate that the compound is promising functional luminescence probe for CrO42–, Cr2O72–, and MnO4–. The mechanisms of the quenching effect and sensing properties were discussed in detail. [ABSTRACT FROM AUTHOR]

In this work a 1,2,4‐triazole derivative 1‐(4‐aminobenzyl)‐1,2,4‐triazole (abtz) was utilized, one new cadmium(II) coordination polymer, namely [Cd(abtz)I2]n (1) was prepared through the powerful solvo‐thermal synthetic strategy. In compound 1, the abtz building blocks are interlinked through the central CdII ions forming the two‐dimensional (2D) layer coordination framework. Powder X‐ray diffraction (PXRD) characterization also reveals that we have prepared the pure phases of coordination polymer 1. Optical properties have been determined, which can behave the excellent photo‐luminescent emission of coordination polymer 1. Photo‐luminescent experiment also reveals that coordination polymer 1 can behave the highly sensitive detection for acetone molecules with high Ksv value (Ksv = 4.12 ×104 L·mol–1) in the recyclable detection fashion. Additionally, coordination polymer 1 also can behave the highly sensitive detection for pollutant dichromate with excellent quenching efficiency Ksv (Ksv = 2.12 × 104 L·mol–1) and low detection limit [38 × 10–3 mM (S/N = 3)]. UV/Vis, photo‐luminescent lifetime, and PXRD patterns also have been determined to analyze the detection mechanism. [ABSTRACT FROM AUTHOR]

Three new divalent cadmium coordination polymers containing cyclohexyldicarboxylate and pillaring dipyridylamide ligands have been prepared and structurally characterized via single‐crystal X‐ray diffraction. All three compounds exhibited layered structures, but with different topologies and interpenetration schemes. [Cd2(12chedc)2(ebin)(H2O)2]n (1) [12chedc = 1,2‐cyclohex‐4‐ene‐dicarboxylate, ebin = ethylenediamine(bis)isonicotinamide] displays a 2D 3,4‐connected net with (426)(42638) topology, also known as the V2O5 structural type. {[Cd(13cdc)(ebin)]·H2O}n (2) (13cdc = cis‐1,3‐cyclohexanedicarboxylate) showed a rare 2D + 2D → 3D parallel polycatenated system of looped layer networks. {[Cd(13cdc)(hbn)]·H2O}n (3) [hbn = hexanediamine(bis)nicotinamide] manifests a (426)(42678) network, also known as the 3,5L2 net. All three materials were assayed as fluorescent "turn‐off" sensors for the detection of nitrobenzene in solution. Thermal decomposition behavior of the new phases is also discussed. [ABSTRACT FROM AUTHOR]

A cadmium chiral coordination polymer, formulated as [Cd(R-cna)]n (1-D) was constructed under hydrothermal method. Single- crystal X-ray diffraction analysis indicated that 1-D exhibited a 2D layered structure with a point symbol of (47[·63). 1-D was further characterized by infrared spectra, powder X-ray diffraction (PXRD), elemental analysis, thermogravimetric analysis (TGA), and circular dichroism spectra (CD). The second-harmonic generation (SHG) property was investigated. It was also found that the luminescence of 1-D can be quenched by iron ions and trinitrotoluene, indicating its potential application as luminescence sensing material. [ABSTRACT FROM AUTHOR]

A new heterometallic coordination polymer, namely [Cd2Sr(bdc)3(H2O)2]n (1) (H2bdc = terephthalic acid), was synthesized via the solvothermal reaction of Cd(NO3)2, Sr(NO3)2, and H2bdc. The X‐ray structural analysis reveals that compound 1 is a 3D framework based on 1D rod‐shaped heterometallic metal‐carboxylate chains as building subunits. Viewing along the crystallographic c axis, there exist large 1D rhombic channels with effective dimensions of ca. 10.0 × 18.6 Å2. Moreover, compound 1 emits intense luminescence at room temperature. The investigations of luminescence indicated that compound 1 can be served as a luminescence probe for the detection of nitroaromatic explosives. Furthermore, the anticancer activity of 1 was evaluated against three human cancer cells MCF‐7, MDA‐MB‐231, and MDA‐MB‐435S via the MTT assay. [ABSTRACT FROM AUTHOR]

Four novel In3+ and Cd2+ based 1D coordination compounds constructed by double betaine ligands were synthesized and characterized structurally and optically. They assemble into 3D supra‐molecular architectures via different stacking or entanglement of 1D zigzag shaped chains, in which C–H···Cl and C–H···O hydrogen bonding interactions play a dramatic impact. Compound 1 displays a 1D + 1D → 3D four‐connect lvt net with 42·84 topology. Compound 2 assembles into a 3D architecture by inclined stacking of the adjacent zigzag chains. Compound 3 displays a 2D + 2D → 3D inclined polycatenation based on the resulting 2D (6, 3) layers that constructed by 1D chains. Compound 4 displays a 3D supra‐molecular architecture based on 1D chains, which were connected via the hydrogen bonding. Meanwhile, four compounds emit in the range of visible region owing to the intra‐ligand π*→π and/or π*→n electron transition induced florescence. [ABSTRACT FROM AUTHOR]

A series of five new ZnII and CdII mixed-ligand coordination polymers, namely, {[Zn(L1)(4,4'-bpy)]·(ClO4)·2H2O} (1), {[Zn(L2)(4,4'-bpy)0.5]·(ClO4)} (2), {[Zn(L3)(4,4'-bpy)]·(NO3)·2H2O} (3), {[Cd(L4)(4,4'-bpy)0.5(NO3)]·5H2O} (4), and {[Zn(L4)(4,4'-bpy)]·Cl·H2O} (5) [4,4'-bpy = 4,4'-bipyridine, L1 = 4-carboxy-1-(4-carboxybenzyl)pyridin-1-ium chloride, L2 = 3-carboxy-1-(4-carboxybenzyl) pyridin-1-ium chloride, L3 = 4-carboxy-1-(3-carboxybenzyl) pyridin-1-ium chloride, and L4 = 3-carboxy-1-(3-carboxybenzyl) pyridin-1-ium chloride], were obtained by the reactions of the 4,4'-bipyridine with four dicarboxylate zwitterionic pyridine ligands. Single-crystal X-ray structural analyses reveal that the five complexes demonstrate different molecular frameworks coming from various coordination modes and flexibilities of different dicarboxylate zwitterionic pyridine ligands and central metal atoms. Mononuclear twofold dinuclear 2D twofold interpenetrating net for 2, four-coordinate mononuclear twofold interpenetrating 2D layer for 3, mononuclear 2D layer arranged in parallel and with large grids for 4, and twofold trans interpenetrating 2D network for compound 5. The structural diversities in 1-5 indicate that the nature of the ligands and the presence of different metal atoms have a great influence on central metal coordination modes and the structural topologies of the metalorganic molecular architectures. In addition, π···π stacking interactions also play important roles in the final crystal packing and supramolecular frameworks. The powder X-ray diffraction, elemental analysis, and photoluminescence properties of 1-5 were studied, which show that architectures play an important role in emission bands and intensities. [ABSTRACT FROM AUTHOR]

Zinc and cadmium diphenate (dip, biphenyl-2,2'-dicarboxylate) coordination polymers containing conformationally flexible dipyridylamide ligands show diverse chain and layer topologies as determined by single-crystal X-ray diffraction. [Cd(dipH)2(bdin)]n (1) [bdin = N,N'-(butane-1,3-diyl)diisonicotinamide] shows a simple 1D zigzag chain structure. {[Cd(dip)(pdin)(H2O)]·1.25H2O}n (2) [pdin = N,N'-(propane-1,3-diyl)diisonicotinamide] shows bilayer slabs formed by interleaving of (4,4) rectangular grid layers. {[Zn2(dip)2(3-pna)2]· 3H2O}n (3) (3-pna = 3-pyridylnicotinamide) manifests a rare 4-con-nected 1D ribbon topology. {[Cd(dip)(4-ppbp)]·2H2O}n (4) [4-ppbp = propane-1,3-diylbis(piperidine-4,1-diyl)bis(pyridin-4-ylmethanone)] shows a 3,5-connected layer with (426)(42678) 3,5L2 topology. {[Zn4(dip)4(H2O)2(4-ppbp)2]·12H2O}n (5) exhibits 2D 3,6-connected layers with (43)2(466683) kgd topology featuring embedded R(8)A(2) classification 10-membered water clusters. Compounds 1, 4, and 5 undergo violet or blue-violet fluorescence upon ultraviolet irradiation. Thermal decomposition behavior of the new phases is also discussed. [ABSTRACT FROM AUTHOR]

Divalent metal coordination polymers containing the rigid 2,5-thiophenedicarboxylate (tdc) ligand and the conformationally flexible dipyridylamide ligand bis(4-pyridylformyl)homopiperazine (bpfh) show different layer topologies and chirality. As determined by single-crystal X-ray diffraction, {[Cd(tdc)(bpfh)(H2O)] ·3H2O} n ( 1) shows a twofold parallel interpenetrated centrosymmetric (4,4) layered grid structure. {[Zn(tdc)(bpfh)] ·H2O} n ( 2) exhibits a similar system of twofold interpenetrated (4,4) grid-like layers, but in contrast to 1, it crystallizes in an acentric space group. {[Ni2(tdc)2(bpfh)2(H2O)] ·2H2O} n ( 3) possesses {Ni2(μ-H2O)(OCO)2} dimeric units connected into a doubled layer motif by the full span of the tdc and bpfh ligands. Weak antiferromagnetic coupling is observed within the dimeric units in 3 [ g = 2.172(6) and J = -0.79(1) cm-1]. Compounds 1 and 2 undergo blue-violet fluorescence upon ultraviolet irradiation; the cadmium derivative 1 shows potential as a sensor for the solution-phase detection of nitrobenzene although coordination polymer exfoliation likely occurs. Thermal decomposition behavior of the three new phases is also discussed. [ABSTRACT FROM AUTHOR]

Four CdII metal coordination polymers, namely, [Cd(HL)(H2O)3] n ( 1), [Cd(HL)(4,4′-bpy)] n · nH2O ( 2), [Cd3(L)2(2,2′-bpy)3(H2O)3] n ·2 nH2O ( 3), and [Cd3(L)2(phen)2(H2O)] n ·2.5 nH2O ( 4) [H3L = 3-(3-carboxyphenoxy) phthalic acid, 4,4′-bpy = 4,4′-bipyridine, 2,2′-bpy = 2,2′-bipyridine, phen = 1,10-phenanthroline], were synthesized and structurally characterized by X-ray diffraction, elemental analysis, and IR spectroscopy. Single-crystal X-ray analyses reveal that complexes 1- 3 have different one-dimensional (1D) chain structures including zigzag chain, ladder chain, and helical chain, whereas complex 4 shows a 0D trinuclear motif. These low-dimensional complexes are further extended to 3D supramolecular networks by intermolecular π-π interactions and hydrogen bonds. The ligand H3L exhibits five coordination modes: μ1-η2-chelating/μ1-η2-chelating, μ1-η2-chelating/μ1-η2-chelating/μ1-η2-chelating, μ1-η2-chelating/μ1-η2-chelating/μ1-η1-bridging, μ1-η2-chelating/μ2-η2-bridging/μ2-η1:η1-bridging, and μ2-η2-chelating:η1-bridging/μ2-η2-chelating:η1-bridging/μ1-η1-bridging. Moreover, the photoluminescent properties of complexes 1- 4 were studied in the solid-state at room temperature. [ABSTRACT FROM AUTHOR]

The d10 coordination polymers (CPs), [Zn(L1)(OH)]n (1) and [Cd(L2)2]n (2) were obtained from isomeric ligands 3-(6-aminpyridinium-3-yl) benzoic acid (L1) and 4-(6-aminpyridinium-3-yl) benzoic acid (L2), and characterized by elemental analyses, IR spectroscopy, single-crystal and powder X-ray diffraction. In compound 1, a spiral chain structure connected by µ2-OH- and the ZnII ions, which are further linked by the L1 ligands to give atwo-dimensional layered structure. Classical hydrogen-bonding interactions (O···H-N) between adjacent layers result in three-dimensional supramolecular structure. Compound 2 features a three-dimensional framework formed by linking [Cd2(COO)2] clusters in a bcu net. Thermal stabilities and fluorescent properties of 1 and 2 were also investigated. [ABSTRACT FROM AUTHOR]

Three coordination polymers, namely {[Cu(5-nipa) (L22)](H2O)2}n (1), [Zn(5-nipa)(L22)(H2O)]n (2), and {[Cd2(5-nipa) 2(L22)(H2O)3](H2O)3.6}n (3), were prepared under similar synthetic method based on 1,2-(2-pyridyl)-1,2,4-triazole (L22) and ancillary ligand 5-nitro-isophthalic acid (5-H2nipa) with CuII, ZnII, and CdII perchlorate, respectively. All the complexes were characterized by IR spectroscopy, elemental analysis, and powder X-ray diffraction (PXRD) patterns. Single-crystal X-ray diffraction indicates that complexes 1 and 2 show similar 1D chain structures, whereas complex 3 exhibits the 2D coordination network with hcb topology. The central metal atoms show distinct coordination arrangements ranging from distorted square-pyramid for CuII in 1, octahedron for ZnII in 2, to pentagonal- bipyramid for CdII in 3. The L22 ligand adopts the same (η3,μ2) coordination fashion in complexes 1-3, while the carboxyl groups of co-ligand 5-nipa2- adopt monodentate fashion in 1 and 2 and bidentate chelating mode in 3. These results indicate that the choice of metal ions exerts a significant influence on governing the target complexes. Furthermore, thermal stabilities of complexes 1-3 and photoluminescent properties of 2 and 3 were also studied in the solid state. [ABSTRACT FROM AUTHOR]

Cadmium(II) based 2D coordination polymer [Cd(L1)2(DMF)2] ( 1) (L1 = 4,5-dicyano-2-methylimidazolate, DMF = N,N′-dimethylformamide) and 2D cobalt(II)-imidazolate framework [Co(L3)4] ( 2) (L3 = 4,5-diamide-2-ethoxyimidazolate) were synthesized under solvothermal reaction conditions. The materials were characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis, powder X-ray diffraction measurement (PXRD) and single-crystal X-ray diffraction. Compound 1 has hexacoordinate CdII ions and forms a zigzag chain-like coordination polymer structure, whereas compound 2 exhibits a 2D square grid type structure. The thermal stability analysis reveals that 2 showed an exceptional thermal stability up to 360 °C. Also, 2 maintained its fully crystalline integrity in boiling water as confirmed by PXRD. The solid state luminescent property of 1 was not observed at room temperature. Compound 2 showed an independent high spin central CoII atom. [ABSTRACT FROM AUTHOR]

Two CdII-containing coordination polymers based on a multidentate N-donor ligand and two structure-related dicarboxylate ions, namely, [Cd2(3,4′-tmbpt)( o-bdc)2] ·2H2O ( 1) and [Cd2(3,4′-tmbpt)2( p-bdc)2] ·6.5H2O ( 2) [3,4′-tmbpt = 1-((1 H-1,2,4-triazol-1-yl)methyl)-3-(4-pyridyl)-5-(3-pyridyl)-1,2,4-triazole, o-H2bdc = 1,2-benzenedicarboxylic acid, and p-H2bdc = 1,4-benzenedicarboxylic acid], were prepared under hydrothermal conditions. The structures of the two compounds were determined by single-crystal X-ray diffraction analysis and further characterized by infrared spectra (IR) and elemental analysis. Compound 1 is a 3D framework containing infinite Cd-O chains. Compound 2 displays a 2D → 2D interdigitated architecture. The effect of the dicarboxylate ions on the structures of the compounds was discussed. Moreover, the optical bandgaps and photoluminescent properties of the compounds were investigated. [ABSTRACT FROM AUTHOR]

ZnII and CdII coordination polymers with dicarboxylate and imidazole-containing ligands, namely, [Cd (2,3-PDC)(L)] n ( 1) and {[Zn(3,4-PDC) (L)0.5] ·H2O} n ( 2), [2,3-H2PDC = 2,3-pyridine dicarboxylate, 3,4-H2PDC = 3,4-pyridine dicarboxylate, and L = 1,4-bis(2-methylimidazol-3-ium-1-yl)biphenyl], were prepared and characterized by elemental analysis, IR spectroscopy, and X-ray diffraction. Complex 1 shows a three-dimensional (3D) structure with threefold interpenetrating diamond topology. Complex 2 features a 3D framework with twofold interpenetrating dmc topology. Moreover, the luminescent properties of complexes 1 and 2 were also investigated. [ABSTRACT FROM AUTHOR]

Hydrothermal reactions of Cd(OAc)2 ·2H2O with 1,2-naphthalic anhydride in the absence/presence of different rigid/flexible bis(pyridyl) co-ligands, produce three distinct coordination polymers, namely [Cd(ndc)] n ( 1), {[Cd5(ndc)4(bpp)2(OH)2](H2O)4} n ( 2), and [Cd5(ndc)4(bpy)2(OH)2] n ( 3) [ndc = 1,2-naphthalenedicarboxylate, bpp = 1,3-bis(4-pyridyl)propane, and bpy = 4,4′-bipyridine]. Complex 1 contains dinuclear [Cd2O2] clusters as secondary building units (SBUs) and shows a two-dimensional (2D) kgd network. Complexes 2 and 3 possess one-dimensional (1D) chains based on pentanuclear [Cd5(μ3-OH)2(COO)2] units as SBUs, which are further extended to afford 2D sql sheet via flexible bpp in 2 and three-dimensional (3D) pcu network via rigid bpy in 3, respectively. The structural diversities indicate that the bis(pyridyl) co-ligands with different flexibility play a key role on the formation of the final supramolecular structures. The complexes were characterized by X-ray crystallographic, IR, elemental, thermal stability, and powder X-ray diffraction analyses. In addition, the photoluminescent properties in solid state were also investigated. [ABSTRACT FROM AUTHOR]

Two coordination polymers, [Cd(Heidc)(bpp)] n ( 1) and [Zn3 (eidc)2(bpp)(H2O)2] ·2H2O} n ( 2) (H3eidc = 2-ethyl-4,5-imidazole dicarboxylic acid, bpp = 1,3-bis(4-pyridyl)propane) were hydrothermally synthesized and characterized by elemental analysis, IR, spectroscopy single-crystal X-ray diffraction, and thermogravimetric analyses. Compound 1 features a 2D layer formed by C-H ···π stacking interactions between adjacent chains, whereas compound 2 shows a 3D (83)2(85.10)-tfc framework constructed of the 2D (6,3) layer. The result demonstrates that the central metal atoms play a key role in governing the coordination motifs. Moreover, solid-state properties such as thermal stabilities and photoluminescence of 1 and 2 were also investigated. [ABSTRACT FROM AUTHOR]

Reaction of Cd(NCS)2 with pyridine in water accidently lead to the formation of crystals of a fourth modification of [Cd(NCS)2(pyridine)2] n, which most likely corresponds to form I reported by Taniguchi et al. but which was not structurally characterized by these authors. This modification crystallizes in the monoclinic space group C2/ c with a = 10.6032(3) Å, b = 15.8676(5) Å, c = 26.2795(8), b = 96.001(2) °and V = 4397.2(2) Å3. The structure of this compound is very similar to that of form III reported recently, in which the Cd cations are octahedrally coordinated by two pyridine ligands and four thiocyanato anions. The cations are linked by pairs of anionic ligands into chains, in which the thiocyanato anions are always trans-coordinated. Further investigations show that larger amounts of pure form I cannot be prepared because it is always contaminated with form II, in which the thiocyanato anions are cis-coordinated. Solvent mediated conversion experiments using mixtures of the trans-modifications I and III as well as the cis-modification II prove that form III disappears first and therefore, is less stable than the second trans-modification I. IR and Raman spectroscopic investigations show, that all forms cannot be distinguished from each other using these methods. [ABSTRACT FROM AUTHOR]

Abstract. Two coordination polymers, namely, {[Cd(cdpc)(hmt)(H2O)] ·H2O} n ( 1), and [Mn(Hcdpc)2(4, 4′-bpy)(H2O)] n ( 2), were constructed by synergistic assembly through the mixed-ligand synthetic strategy (H2cdpc = 1-carboxymethyl-3, 5-dimethyl-1H-pyrazole-4-carboxylic acid, hmt = hexamethylenetetramine, and 4, 4′-bpy = 4, 4′-dipyridine). Their structures were determined by single-crystal X-ray diffraction analyses and further characterized by elemental analyses, IR spectra, powder X-ray diffraction (PXRD), and thermogravimetric (TG) analyses. Single X-ray diffraction analysis reveals that complex 1 is a 2D 4-connected sql sheet, and complex 2 is an interesting 1D loop chain. The two complexes are further expanded to 3D supramolecular structure through non-covalent bonds. Besides, luminescent properties of two complexes in the solid state and magnetic property of 2 were also investigated. [ABSTRACT FROM AUTHOR]

The three-dimensional (3D) coordination polymer {[Cd2(4,4′-sdb)2(tib)(H2O)3] ·H2O} n ( 1) [4,4′-H2sdb = 4,4′-sulfonyl-dicarboxylic acid and tib = 1,3,5,-tris(1-imidazolyl) benzene] was prepared by the combination of a V-shaped 4,4′-sulfonyl-dicarboxylic acid and neutral organonitrogen coligands. The structure of the neutral polymeric complex 1 was determined by single-crystal X-ray diffraction studies. Complex 1 exhibits a twofold interpenetrated (3,3,4)-connected 3D architecture with the point symbol (6.82).(64.82).(83). In addition, the luminescent property of complex 1 was investigated. [ABSTRACT FROM AUTHOR]