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Two new compounds namely [Zn(L1)phen] 3 1 and Ni(L1)phen(MeOH) 2 (L1 = 3, 5-dichlorosalicylaldehyde thiosemicarbazone) were synthesized by the slow evaporation method at room temperature. The structure of ligand L1 was determined using 1H NMR and 13C NMR spectra. X-ray single crystal diffraction analysis revealed that compounds 1 – 2 can form 3D supramolecular network structures through π ··· π stacking and hydrogen bonding interactions. The DFT calculation shows that the coordination of ligand and metal is in good agreement with the experimental results. Hirshfeld surface analysis revealed that H...H and Cl...H interactions were the predominant interactions in compounds 1 – 2. Energy framework analysis indicated that dispersion energy played a dominant role in the energy composition of compounds 1 – 2. The inhibitory effects of compounds 1 – 2 against Escherichia coli (E. coli) and Methicillin-resistant Staphylococcus aureus (MRSA) were tested using the paper disk diffusion method (1 : E. coli: 18 mm, MRSA: 17 mm, 2 : E. coli: 15 mm, MRSA: 16 mm). Ion releasing experiments were conducted to assess the ion release capacity of compounds 1 – 2 (Zn2+, 4 days, 38.33 µg/mL; Ni2+, 4 days, 29.12 µg/mL). Molecular docking demonstrated the interaction modes of compounds 1 – 2 with UDP- N -acetylenolpyruvoylglucosamine reductase (MurB) and dihydrofolate reductase (DHFR) in bacteria, involving hydrophobic, stacking, hydrogen bonding and halogen bonding interactions. The generation of reactive oxygen species (ROS) in bacteria under the presence of compounds 1 – 2 were evaluated using a fluorescent dye known as dichlorodihydrofluorescein diacetate (DCFH-DA). Potential antibacterial mechanisms of compounds 1 – 2 were proposed. [Display omitted] • Two new compounds [Zn(L1)phen] 3 1 and Ni(L1)phen(MeOH) 2 were synthesized under room temperature. • Compounds 1 – 2 were both extended into a 3D supermolecule network structure via π ··· π stacking and hydrogen bonding interactions. • Compounds 1 – 2 were both potential antibacterial bacterial for E. coli and MRSA (1 : E. coli: 18 mm, MRSA: 17 mm, 2 : E. coli: 15 mm, MRSA: 16 mm). • Molecular docking of protein and DNA for compounds 1 – 2 were investigated. • The potential antibacterial mechanism of compounds 1 – 2 was proposed via combining with theoretical calculation and experimental results. Two new compounds namely [Zn(L1)phen] 3 1 and Ni(L1)phen(MeOH) 2 (L1 = 3, 5-dichlorosalicylaldehyde thiosemicarbazone) were synthesized by the slow evaporation method at room temperature. The structure of ligand L1 was determined using 1H NMR and 13C NMR spectra. X-ray single crystal diffraction analysis revealed that compounds 1 – 2 can form 3D supramolecular network structures through π ··· π stacking and hydrogen bonding interactions. The DFT calculation shows that the coordination of ligand and metal is in good agreement with the experimental results. Hirshfeld surface analysis revealed that H...H and Cl...H interactions were the predominant interactions in compounds 1 – 2. Energy framework analysis indicated that dispersion energy played a dominant role in the energy composition of compounds 1 – 2. The inhibitory effects of compounds 1 – 2 against Escherichia coli (E. coli) and Methicillin-resistant Staphylococcus aureus (MRSA) were tested using the paper disk diffusion method (1 : E. coli: 18 mm, MRSA: 17 mm, 2 : E. coli: 15 mm, MRSA: 16 mm). Ion releasing experiments were conducted to assess the ion release capacity of compounds 1 – 2 (Zn2+, 4 days, 38.33 µg/mL; Ni2+, 4 days, 29.12 µg/mL). Molecular docking demonstrated the interaction modes of compounds 1 – 2 with UDP- N -acetylenolpyruvoylglucosamine reductase (MurB) and dihydrofolate reductase (DHFR) in bacteria, involving hydrophobic, stacking, hydrogen bonding and halogen bonding interactions. The generation of reactive oxygen species (ROS) in bacteria under the presence of compounds 1 – 2 were evaluated using a fluorescent dye known as dichlorodihydrofluorescein diacetate (DCFH-DA). Potential antibacterial mechanisms of compounds 1 – 2 were proposed. [ABSTRACT FROM AUTHOR]

To search for more high-performance crystalline proton conducting materials and to accelerate the related research progress, in this paper, a one-dimensional coordination polymer (CP), [Co(BBOT) 2 (H 2 O) 3 ·2H 2 O] n (1) (H 2 BBOT = N-benzoyl-N′-(4-benzoxy)thiourea) was firstly prepared by solvent volatilization approach. Subsequently, the thermal, H 2 O and chemical stabilities of the CP were tested and its high structural stability was confirmed. Furthermore, in 1 , a stable solid three-dimensional framework can be constructed by intermolecular H-bonds and stacking interactions between phenyl units. Then, utilizing the AC impedance determination, the dependence of the proton conductivity of this CP on temperature and humidity in the water vapor environment was explored and the positive correlation was verified. Excitingly, the optimized proton conductivity of this compound under specific test conditions (100 °C/98 % relative humidity) can be as high as 10−4 S/cm, being in the forefront of similar crystalline solid materials. Finally, according to the value of activation energy and the characteristics of crystal structure, we speculate on the proton conduction mechanism. Proton conductivity of a CP under variable humidity and temperatures was explored. Its highest proton conductivity can attain up to 10−4 S/cm, and its proton-conduction mechanism was speculated. [Display omitted] • One carboxylate-based Co(II) coordination polymer was prepared. • Its structure was characterized by single-crystal X-ray diffraction. • Its water-assisted proton conduction was explored. • The proton-conducting mechanism was speculated. [ABSTRACT FROM AUTHOR]

Abstract Four new coordination polymers, namely, [Zn 2 (L) 2 (1,3-bdc)(H 2 O) 2 ] n (1) , [Cd 2 L 2 (Cl) 2 ] n ·0.5nH 2 O (2) , [Cd 2 L 2 (adip)] n ·2nH 2 O (3) , and [CdLCl] n (4) were solvothermally synthesized by reaction of Zn(NO 3) 2 ·6H 2 O, CdCl 2 ·H 2 O with an asymmetrical rigid N-heterocyclic carboxylatic acid (HL), where HL = 1-(4-carboxylphenyl)-3-(prazin-2-yl)-1H-1,2,4-triazole, 1,3-bdc = benzene- 1,3-dicarboxylic acid, H 2 adip = adipic acid, H 2 glu = glutaric acid. Compound 1 is a 1D ladder chain. Compound 2 is a (3,6)-connected network with the Point symbol of (42·6) 2 (44·62·88·10). Compound 3 displays a intriguing (3,3,4,4)-connected topological net with the Point symbol of (4·64·8)(4·72)(42·6·72·9)(42·6). Compound 4 presents a new (3,5)-connected topological net with the Point symbol of (3·4·5)(32·4·5·62·74). In addition, the thermal stabilities and photoluminescence properties of these compounds were also studied. Dramatically, compound 3 shows the high selectivity and sensitivity for Fe3+ cation via a luminescence quenching effect. Graphical abstract In this paper, we have synthesized four new Zn/Cd compounds based on HL, namely, [Zn 2 (L) 2 (1,3-bdc)(H 2 O) 2 ] n (1) , [Cd 2 L 2 (Cl) 2 ] n ·0.5nH 2 O (2) , [Cd 2 L 2 (adip)] n ·2nH 2 O (3) , [CdLCl] n (4). Meanwhile, the luminescence properties and thermal stabilities of 1 – 4 were also studied. Compound 3 shows the high selectivity and sensitivity for Fe3+ cation, via a luminescence quenching effect. fx1 Highlights • Four new coordination polymers were solvothermally synthesized. • HL ligand displays multiple coordination modes. • Compound 3 shows the high selectivity and sensitivity for Fe3+ cation. [ABSTRACT FROM AUTHOR]

Abstract Nitrogen-rich coordination polymers have attracted much attention recently since they were immerged as energetic materials. Despite plenty of novel energetic coordination polymers (ECPs) were reported, their structure-property relationships were seldom investigated. In this study, two new ECPs [Cu(DOBT)(H 2 O) 2 ] n (1) and {[Cu 2 (DOBT) 2 ](tma)} n (2) with 1D and 3D crystal structures have been synthesized by using 1H,1′H-[5,5′-bitetrazole]-1,1′-diol (DHBT) and Cu(II) ions in different solvent systems, respectively. The crystal structures, sensitivity, thermal decomposition behaviors, as well as detonation performances of these two ECPs were investigated carefully. The detonation performances were calculated with EXPLO5. This research comparatively studied the structure-property relationships of ECPs composed of the same ligand and metal ion for the first time which may guide design and synthesis of new ECPs with specific properties. Graphical abstract Comparative study the structure-property relationships of two nitrogen rich energetic coordination polymers (CPs) composed of the same ligand and metal ion reveals that 3D CP has lower sensitivity, higher thermostability and higher heat of detonation. The high-density 1D CP exhibits higher detonation velocity and pressure than that of 3D one. fx1 Highlights • In this paper, the structure-property relationships of energetic coordination polymers (ECPs) composed of the same ligand and metal ion were studied for the first time. • The results show that 3D CP has lower sensitivity, higher thermostability and higher heat of detonation. • However, the high-density 1D CP exhibits higher detonation velocity and pressure than that of 3D one. • The results may guide design and synthesis of new ECPs with specific properties. [ABSTRACT FROM AUTHOR]

In this paper, two new H 2 ZTO-Co(II) coordination polymers (H 2 ZTO = 4,4′-azo-1,2,4-triazol-5-one), [Co(H 2 ZTO) 2 (H 2 O) 4 ](NO 3 ) 2 (1) and {[Co(H 2 ZTO)(H 2 O) 4 ](NO 3 ) 2 ·2H 2 O} n (2), have been synthesized and characterized. Polymer 2 is derived from 1 and undergoes a multistage transformation by soaking 1 in distilled water. X-ray single crystal structure analyses showed that 2 exhibit a one-dimensional (1D) chain geometry coordinated by 0D units of 1 through uncoordinated nitrogen atoms of H 2 ZTO ligands. The thermal decomposition behaviors and magnetic properties of 1 and 2 were discussed. In addition, the low-temperature (1.9–300 K) heat capacities of 1 and 2 were measured using the heat capacity option of a Quantum Design Physical Property Measurement System (PPMS). The thermodynamic functions of 1 in the experimental temperature range were derived by fitting the heat capacity data to a series of theoretical and empirical models. Using the fitted heat capacity results, the standard molar entropy and standard molar enthalpy have been respectively calculated to be (871.1 ± 8.7) J·mol −1 ·K −1 and (132.7 ± 1.3) kJ·mol −1 for 1 . [ABSTRACT FROM AUTHOR]

In this paper, we reported the fabrication of Co-embedded nitrogen-doped carbon nanotube (Co-NCNT) by using Co-melamine coordination polymer (CP) as precursor. The sample was well characterized via SEM, TEM, XRD, XPS and BET methods. The Co-NCNT shows excellent and stable catalytic performance for OER. The overpotential of Co-NCNT at 10 mA cm -2 is 370 mV (vs RHE). The current density of Co-NCNT could reach 100 mA cm -2 at overpotential of 520 mV, which showed much better performance than RuO 2 , while the largest current density of RuO 2 could reach is only 44 mA cm -2 . The Tafel slope of Co-NCNT is 56 mV dec -1 , which is smaller than that of commercial RuO 2 (58 mV dec -1 ). The results indicate that metal-melamine based CPs or MOFs can be promising precursors for the preparation of efficient metal-embedded nitrogen-doped carbon materials for electrocatalysis. [ABSTRACT FROM AUTHOR]

Coordination chemistry of pyridinyl-hexahydropyrimidine has not been studied to date, despite that the organic chemistry and coordination chemistry involving rigid bispyridine (bipy), pyrimidine and their derivatives have been widely reported. In this paper, the one-pot reaction of AgX (X = NO 3 − and ClO 4 − ) with three rigid-flexible bispyridine analogues, 2-(pyridin- n -yl)hexahydropyrimidine [n =4 ( L1 ), 3 ( L2 ), 2 ( L3 )], lead to the formation of seven complexes, namely, [AgL1(NO 3 )] n ·n(H 2 O) ( 1 ), [AgL1(NO 3 )] n ( 2 ), [Ag 6 (L1) 4 (NO 3 ) 6 ]·6(H 2 O) ( 3 ), [AgL1(CH 3 CN)] n ·n(ClO 4 ) ( 4 ), [Ag 2 (L2) 2 (NO 3 )(H 2 O)] n ·n(NO 3 )·n(H 2 O) ( 5 ), [Ag 3 (L2) 3 (CH 3 CN) 2 ] n 0.3n(ClO 4 ) ( 6 ), and [Ag 2 (L3) 2 (NO 3 ) 2 ] ( 7 ), which have been characterized by elemental analysis, IR, TG, PL, powder and single-crystal X-ray diffraction. Structural analyses indicate that the conformational transformations of L1-L3 cause diverse structures. In 1 and 2 , L1 presents modes I and II which connects adjacent Ag(I) into fes layers. In contrast, modes III and I in 3 and 4 join adjacent Ag(I) into hexanuclear and ladder chain structures. Complexes 5 and 6 show the same ladder chain structures with the L2 displaying the same coordination mode IV. L3 in 7 exhibits tripodal mode V to connect adjacent two Ag(I), thus forming dinuclear unit. Interestingly, adjacent dinuclear units are further joined by intermolecular hydrogen bonds to form kgd layer. Luminescent investigation reveals that 4 and 6 exhibit emissions from 443 to 581 nm. [ABSTRACT FROM AUTHOR]

In this paper, a series of metal-organic frameworks (MOFs), namely, [Co(pip)(4,4′-bpy)] n (1), [Co 2 (pip) 2 (bibp)] n (2), [Mn(pip)bidmp] n (3) and [Ni(pip)(bibp)(H 2 O)] n (4) (bpy ​= ​4,4′-bipyridine, bibp ​= ​4,4-bis(imidazolyl)biphenyl, bidmb ​= ​1,4-bis(1-imidazoly)-2,5-dimethylbenzene), have been solvothermally synthesized based on the main ligand 6-(3-pyridyl)isophthalic acid (H 2 pip) and structurally characterized by various methods. These MOFs all present three dimensional (3D) pillared-layer frameworks, and through systematic modulation of auxiliary ligands and metal ions, their structures can be well regulated from nonporous to porous. Considering their excellent thermal and water stability, the dye removal properties from water solutions of these MOFs were further studied, and notably, 2 which has the largest porosity of the four MOFs, exhibits very fast selective adsorption of methyl orange over Rhodamine B (MO/RhB) with a total MO uptake amount of 83.4 ​mg ​g−1. Moreover, the catalytic CO 2 transformation properties of these MOFs were also carried out under mild conditions, of which 2 exhibited the highest catalytic activity with 69.57% yield for propylene carbonate and 50.55% for butylene carbonate, respectively. [Display omitted] • Four 3D pillared-layer MOFs, namely 1 – 4 , have been synthesized by systematic modulation of auxiliary ligands and metal ions. • All of the four MOFs reveal excellent hydrothermal stability. • 2 exhibits superior behavior in fast selective MO adsorption over RhB and CO 2 catalytic conversion processes. • The unique framework structures endow compound 2 with multifunctional applications. [ABSTRACT FROM AUTHOR]

One-pot three-component Arbuzov-type reaction, involving anhydrous cadmium acetate, dimethyl sulfite, and tetraethylammonium iodide, has produced the cadmate salt, [Et 4 N] 2 [Cd(OMs) 4 ] (1) revealing weakly-coordinating methanesulfonate (OMs) ligands inside the metal-coordination sphere. The 'ate' salt 1 was found useful as a precursor in the preparation of coordination polymers with compositions, [Cd(OMs) 2 (MeOH)] n (2) and [Cd(OMs) 2 (H 2 O) 2 ] n (3), when subjected to crystallization in a methanol/chloroform mixture, in dry and ambient conditions, respectively. Compounds 1–3 were characterized by spectroscopic [1H, 13C NMR, FT-IR] techniques, and elemental and thermogravimetric analysis, while the structural attributes of 2 and 3 were investigated using single-crystal X-ray diffraction. The composition of 1 was further scrutinized by electrospray-ionization mass-spectrometry (ESI-MS). The crystal structure of 2 exhibits formation of a two-dimensional (2-D) layer facilitated by the bidentate (μ 2) and tridentate (μ 3) modes of coordination of sulfonate ligands around the metal center. The structure of 3 demonstrates the formation of 1-D linear chains, comprising of eight-membered cyclic [−Cd–O–S–O−] rings, owing to the bridging bidentate (μ 2) mode of coordination of the sulfonate ligands. The involvement of hydrogen-bond interactions in 2 and 3 further perpetuates the assemblies into 2-D and 3-D supramolecular coordination polymers, respectively. This paper reports noticeable features such as, (a) cadmate dianion was afforded by the in situ generation of methanesulfonate ligands and subsequent complexation to the Cd(II) atom; (b) ability of alkanesulfonate ligand to display flexible coordinating behaviour [(μ 2 and uncommon (μ 3)] and prolific H-bond acceptor; (c) competitive ligation between strong coordinating solvents (MeOH and H 2 O) and weakly-coordinating methanesulfonate ligands; (d) effect of types and number of solvent molecules around the metal center with their participation in non-covalent interactions in bringing variation in the structural outcome; (e) the values of distances of Cd–O bonds in 1 and 2 fall in the range of 2.24 Å to 2.29 Å, suggesting the presence of direct metal-sulfonate interactions. The dispersion-corrected density functional theory (DFT-D) and Bader's quantum theory of atoms in molecule (QTAIM) (primary and secondary) studies explored the structures, electronics, and non-covalent interactions of compounds 2 and 3. Additionally, among different involved non-covalent interactions, Hirshfeld surface analysis emphasized the presence of O⋯H/H⋯O contacts as the dominant intermolecular non-covalent interactions as the consolidating factor in crystal packing, in both compounds. Structural variations in Cd(II) coordination polymers based on weakly-coordinating methanesulfonate ligand are tuned by the combined effect of solvents, ligand coordination modes, and non-covalent interactions. Image 1 • Synthesis and characterization of a new cadmate salt used for the construction of coordination polymers. • The compounds are characterized by FT-IR, 1H, 13C, elemental techniques. • Crystallographic study reveals direct Cd(II)-methanesulfonate bonds and non-covalent interactions in construction of 2D/3D supramolecular motifs. • Structural outcomes depend upon the combined effect of solvent molecules, ligand coordination, and non-covalent interactions. • DFT and Hirshfeld surface study are used to understand structural and non-covalent interactions. [ABSTRACT FROM AUTHOR]