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To systematically explore the effects of polynuclear complexes on the removal of chromium pollutants, a new three-dimensional (3D) microporous metal-organic compound [Cd 3 (HCO 2) 2 (dpa) 4 (bpp) 3 ] n (dpa ​= ​diphenic acid, bpp ​= ​1,3-bi(4-pyridyl)propane) (1) was prepared through hydrothermal synthesis. The structure was characterized by X-ray single crystal diffraction, elemental analysis, and Fourier transform infrared spectroscopy. The results indicate that complex 1 based on Cd(II) clusters is monoclinic and consists of the C 2/ c space group. It exhibits a new 2-nodal (3,5)-connected 3D framework with a Schläfli symbol of {43}{45, 65}. The thermogravimetric analysis (TGA) reveals complex 1 has high thermal stability (stable until 490 ​°C). The photoluminescence shows the emission wavelength of the fluorescence is red-shifted (30 ​nm), and the intensity is significantly increased compared to the free ligand. Adsorption analysis shows that the Cd(II) compound demonstrates significant adsorption towards the dichromate anion (Cr 2 O 7 2−). Its adsorption isotherm is consistent with the Langmuir model and its adsorption kinetics follows a pseudo-second-order model. 3D polynuclear Cd(II) complexes exhibit photo-fluorescent property and adsorption towards the dichromate anion. Image 1 • A new polynuclear coordination polymer [Cd 3 (HCO 2) 2 (dpa) 4 (bpp) 3 ] n has been prepared and characterized. • Cd(II) clusters with 1D+2D→3D framework and a new 2-nodal (3,5)-connected topology. • Robust microporous 1D channel for dichromate removal in an aqueous solution. [ABSTRACT FROM AUTHOR]

Xylene-functionalized N-donor ligand p -BIMB (p = para position, BIMB = bis- (imidazole-1-ylmethyl)benzene) and rigid carboxylate linker trans -H 2 CHDA (CHDA = 1,4-cyclohexane(dicarboxylic)acid) were treated with Co(NO 3) 2 under solvothermal conditions to afford a new two-dimensional (2D) coordination polymer [Co(trans -H 2 CHDA) 2 (p -BIMB) 2 ·2H 2 O] n (1). Complex 1 possesses a sql network. With the porosity formed by the 2D framework, the Co(II) complex 1 demonstrates an excellent specific capacitance of 563 F g−1 at a current density of 1 A g−1, and also good retention of capacitance (≈64% after 4000 cycles at 5 A g−1). Which make complex 1 a good candidate for electrode material in a supercapacitor application. Meanwhile, this Co(II) compound exhibits good adsorption ability for the permanganate anion. Image 1 • A new coordination polymer [Co(trans -H 2 CHDA) 2 (p -BIMB) 2.•2H 2 O] n has been prepared and characterized. • 2D network with a 4,4-sql topology. • Stable metal organic framework for permanganate recognition and removal in an aqueous solution. • Good candidate for electrode material in a supercapacitor application. [ABSTRACT FROM AUTHOR]

• Three new coordination polymers based on rigid tripodal TIPA ligands have been successfully prepared and characterized. • Unique feature of an interpenetrating 2D network, 2D + 2D → 3D, in two opposite spiral channels. • Good candidate for detection and removal of environmentally hazardous industrial pollutants. • Fluorophores for nitroaromatics- and Fe3+-selective sensing. Three new metal–organic complexes [Cd(TIPA)(suc) 0.5 (NO 3)·½H 2 O] n (1), [Ni(TIPA)(tda) 0.5 (H 2 O)·¼H 2 O] n (2) and [Cd(TIPA)(tda) 0.5 ·1½H 2 O] (3) were synthesized via rigid tripodal ligand tris(4-(1H-imidazol-1-yl)phenyl)amine (TIPA) and three dicarboxylic acids either succinic acid (H 2 suc) or 2,5-thiophenedicarboxylic acid (H 2 tda). Crystallographic data for 1 – 3 reveal three-dimensional (3D) networks and channels in the structures. The structure of 2 is unique featuring an interpenetrating 2D network, 2D + 2D → 3D, with the two associated 2D networks existing in two opposite spiral channels. TGA plots exhibit a loss of mass corresponding to the loss of the solvated water molecules in the 100–200 °C temperature region and begin to lose additional fragments only at T > 300 °C revealing the robust nature of the 3D framework in the complexes. The metal-organic frameworks (MOFs) are screened for their potential application in the detection and removal of environmentally hazardous industrial pollutants. Fluorescence emission spectra for 1 and 2 show that the two MOFs are capable of sensing nitrobenzene (NB), with the nickel complex 2 exhibiting significantly higher sensing ability. Powder XRD data measured for 1 and 2 and those of NB-treated 1 and 2 show significant differences in their patterns, providing further support for the strong interaction between the MOF complexes and NB. The fluorescence emission observed for 1 is more effectively quenched by the presence of Fe3+ than any of 17 other metal ions investigated. Complex 3 possesses some ability to adsorb inorganic pollutants. [ABSTRACT FROM AUTHOR]

A series of three-dimensional coordination polymers, namely, [Cd(BIMB)(SCA)] n ( 1 ), [M(BIMB)( trans -CHDC)] n ( 2 , M = Cd 2+ ; 3 , M = Co 2+ ), where BIMB = 1,4-di(1 H -imidazol-1-yl)benzene, SCA 2− = succinate dianion, CHDC 2− = cyclohexane-1,4-dicarboxylate dianion) are synthesized hydro/solvatothermal methods. The products are characterized by elemental analysis and single–crystal X-ray diffraction data. Both the dianion and BIMB bridge different pairs of the metal ions, the three complexes are polymeric and their three-dimensional topology feature a diamond-like metal–organic framework (MOF). Owing to the length of the two bridging ligands, moderate size voids are formed in the diamondoid networks. However, the voids are filled by mutual interpenetration of four independent equivalent frameworks in a 5-fold interpenetrating architecture, and there is no sufficient void volume available for any guest molecules. The phase purity and thermal stability of the compounds are verified by powder X–ray diffraction (PXRD) and thermogravimetric (TG) data. The solid–state fluorescence spectra for the 3d 10 Cd 2+ MOF's 1 and 2 reveal significant enhancement in their emission intensities in comparison to the non-metallated BIMB. The enhanced emission is attributed to perturbation of intra-ligand emission states due to Cd 2+ coordination. [ABSTRACT FROM AUTHOR]