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In the current research, the moisture-resistant of Mg-MOF-74 was successfully improved by coating with two-dimensional (2-D) hexagonal boron nitride (h -BN) during the facile hydrothermal synthesis process. Both TEM and SEM results revealed that 2-D h -BN is coated on Mg-MOF-74's surface. The crystal structure, morphology, surface area, thermal stability and CH 4 uptake capacity of Mg-MOF-74 were not drastically influenced by coating with h -BN as examined by XRD, FTIR, SEM, and TEM. Further, the coated Mg-MOF-74 demonstrated better stability than uncoated Mg-MOF-74, when being exposed to high humidity, in terms of surface area and CH 4 uptake capacity. It was observed that the coated Mg-MOF-74 with 1 ​wt % h -BN has reached to 1959 ​m2 ​g−1 surface area and CH 4 uptake capacity of 43 ​cm3 ​g−1 after exposure to high humidity for a duration of 1 month. Thus, this research work has opened a new window towards the improvement of the water stability of Mg-MOF-74. [Display omitted] • The water resistance capacity of Mg-MOF-74 could be improved by coating with two dimensional materials h -BN. • Application of h -BN as coating material of Mg-MOF-74. • h -BN coated Mg-MOF-74 provide high surface area and enhanced CH 4 uptake capacity. • The sample Mg-MOF-74@1 wt.% h -BN exhibited the highest water stability. [ABSTRACT FROM AUTHOR]

Abstract: This work presents six CuII, CoII, and NiII supramolecular complexes assembled from a bent dipyridyl ligand 2,5-bis(3-pyridyl)-1,3,4-oxadiazole (3-bpo) and R-isophthalic acids (R =–CH3 for 5-methylisophthalic acid or R =–OCH3 for 5-methoxyisophthalic acid), which have been prepared using the layer-separation diffusion method and fully characterized by IR, elemental analysis, and powder X-ray diffraction (PXRD) techniques. Single-crystal X-ray diffraction indicates that these complexes show 1-D tube-like (for CuII complexes 1 and 2) or discrete cage-like dinuclear (for CoII and NiII complexes 3–6) coordination patterns. Furthermore, extended 3-D supramolecular architectures are constructed via secondary interactions between the coordination arrays, and three types of packing fashions are observed for the dinuclear species 3–6. Structural diversification for these complexes can be properly attributed to the inherent discrepancy of metal ions and the substituent effect of R-isophthalate tectons. [Copyright &y& Elsevier]

The reaction of 2,5-bis(2-pyridyl)-1,3,4-oxadiazole (L1) with Cu(OAc)2·H2O salt in a CH3OH/CH3CN medium produces a new monometallic copper(II) complex 1 [Cu(L4)(OAc)(H2O)](H2O)2(CH3CN), where HL4=N-(α-hydroxyl-2-pyridyl)-N′-(α-methoxy-2-pyridyl)ketazine (C13H12N4O2), which was characterized by IR, UV–vis and elemental analysis, and established by X-ray diffraction technique. The results reveal that metal-assisted alcoholysis of L1 leads to the open of the central oxadiazole ring to give a new ligand HL4 during this course. In the crystal structure of complex 1, L4 acts as a tridentate chelating anionic ligand to coordinate to the CuII center, which lies in a square-pyramid coordination environment. Additionally, hydrogen-bonding interactions also play an important role in the self-assembly process. The mechanism of the metal-assisted alcoholysis of L1 in formation of complex 1 was discussed in detail and the spectral properties of 1 were also investigated. [Copyright &y& Elsevier]

Sodium praseodymium orthophosphate Na 3 Pr(PO 4 ) 2 was prepared using high temperature molten salt method and structurally characterized by single-crystal X-ray diffraction (SC-XRD) analysis. Its structure can be modeled as a four-dimensional (4D) commensurately modulated structure with orthorhombic superspace group Pca 2 1 (0 1/3 0)000 or as a conventional 3D superstructure description. The structure contains PrO 8 , NaO 6 , NaO 7 and PO 4 polyhedra, which are in six types of linear array along the a -axis. Furthermore, the excitation and emission spectra, decay time and Commission International de l’Éclairage (CIE) chromaticity index of Na 3 Pr(PO 4 ) 2 were studied. Under blue light excitation (468 nm), the powdered Na 3 Pr(PO 4 ) 2 calcined at 1200 °C shows the strongest red emission at around 610 nm, which originates from the 3 P 0 → 3 H 6 and 1 D 2 → 3 H 4 transformations of Pr 3+ ion. [ABSTRACT FROM AUTHOR]

Cobalt(II) and copper(II) complexes with deprotonated N-[2'-(4-methyl)pyrimidinyl]-2-nitrobenzenesulfonylurea were synthesized and their structures were characterized by IR spectrum, elemental analysis and X-ray diffraction. The deprotonated sulfonylurea is a bidentate ligand to Co(II) or Cu(II) in octahedral geometry. In the packing diagrams of the complexes, C-H ··· O hydrogen bonds are observed. The UV and fluorescence spectra of the complexes are described, and the thermogravimetric analyses of the complexes were performed. [ABSTRACT FROM AUTHOR]

Reaction of dilithium derivatives of N,N’-(dimethylsilanediyl)diamines, Me2Si[N(Li)R]2 with benzonitrile followed by treatment with Me2SiCl2 afforded 1,3-bis[1-(N-R-imino)-1-phenylmethyl]-1,3,2,4-diazadisiletidines, the neutral four-membered bissilylene-linked bisamidines, whose structure was established by X-ray diffraction. [Copyright &y& Elsevier]