Guang Fan

Synthesis, crystal structure, and characterization of energetic complex Pb(ATZ)(phen)2 · 3H2O

A new energetic complex, Pb(ATZ)(phen)2·3H2O (1) (ATZ = 5,5′-azotetrazolate), was synthesized and characterized by single crystal X-ray diffraction. Crystal data: monoclinic, P2(1)/n space group, a = 8.4545(1) Å, b = 25.846(2)Å, c = 13.096(2)Å, and β = 102.873(2)°. In addition, elemental analysis, IR, and thermogravimetric analysis are presented. Furthermore, the complex was also explored as an additive to promote thermal decomposition of ammonium perchlorate.

A novel mixed-valence copper coordination polymer: synthesis, characterization and crystal structure

Hydrothermal reaction of copper(II) nitrate trihydrate with 2-pyrazinecarboxylic acid in the presence of phosphorous acid gave a novel mixed-valence coordination polymer, [Cu(I)Cu(II)(C5H3N2O2)2(NO3)(H2O)] n (1), which has been structurally characterized. Crystal data: triclinic, P , a = 6.2266(6), b = 8.0148(7), c = 14.443(1) Å, α = 74.698(1), β = 84.865(1), γ = 84.532(1)°, V = 690.51(11) Å3, Z = 2, R 1 = 0.0262. The complex features linear –Cu(1)(2-pyrazinecarboxylate)–Cu(2)–(NO3)(H2O)(2-pyrazinecarboxylate)–Cu(3) (2-pyrazinecarboxylate)–Cu(2)(NO3)(H2O)(2-pyrazinecarboxylate)– strands cross-linked by water molecules to form a two-dimensional sheet, further connected by intralayer Cu(2) ···  interactions to form a novel cavity. Other characteristic data are given.

catena-Poly[[[tetra­aqua­iron(II)]-μ-5,5′-diazenediylditetra­zolido] dihydrate]

In the title compound, {[Fe(C2N10)(H2O)4]·2H2O}n, the coordination geometry around the Fe(II) atom, which lies on a center of inversion, is distorted octahedral, with bonds to four O atoms and two N atoms. The azotetrazolate ligand displays a bridging coordination mode, forming an infinite zigzag chain. Intermolecular O—H⋯O and O—H⋯N hydrogen bonding and offset face-to-face π–π stacking interactions [centroid–centroid distance = 3.4738 (13) Å] lead to a three-dimensional network.

Water tape stabilized in a 3D porous copper(I) supramolecular network

Through hydrothermal synthesis, Cu(2-pac)2 (2-pac = 2-pyrazinecarboxylic acid) reacting with 4,4′-bipyridine (abbreviated for 4,4′-bpy) in 1 : 1 molar ratio afforded a porous three dimensional supramolecule containing an infinite T4(2)8(2) water tape, showing the contribution of the water tape to the stability of the crystal host and the role of cooperative association between the water tape and the crystal host in the formation of the water tape.

Diaqua­(5-methyl­pyrazine-2-carboxyl­ato-κ2N1,O)iron(II)

In the neutral title complex, [Fe(C6H5N2O2)2(H2O)2], the coordination geometry aound the FeII atom, which lies on an inversion centre, is distorted octahedral comprising two N atoms and two O atoms from two 5-methylpyrazine-2-carboxylate ligands, and two water molecules. The crystal structure is stabilized by a network of O—H⋯O hydrogen bonds, resulting in a two-dimensional supramolecular structure.

Mixed-valence copper coordination polymers based on CuSCN or CuN3 as bridging motifs

Two novel mixed valence copper coordination polymers, [Cu(2-pac)2(CuN3)(H2O)] n (1) and [Cu(2-pac)2(CuSCN)2] n (2), have been prepared through hydrothermal synthesis and analyzed for structure determination, which exhibit two- and three-dimensional structures respectively. In complex (1), zigzag chains of [CuN3] n running parallel to thec direction are interconnected by Cu(2pac)2 to form a two-dimensional layer structure. In complex (2), the arrangement of μ-1,1,3 bridging thiocyanate ligand leads to the formation of ten-membered Cu—SCN— Cu—S—Cu—NCS rings, and each Cu atom is further linked by Cu(2-pac)2 to afford a three-dimensional configuration.

Poly[[diaquadi-μ2-cyanido-bis­(μ2-pyrazine-2-carboxyl­ato)dicopper(I)copper(II)] dihydrate]

In the title compound, {[CuIICuI 2(C5H3N2O2)2(CN)2(H2O)2]·2H2O}n, the CuII atom lies on an inversion centre and is octahedrally coordinated by two N atoms and two O atoms from opposing pyrazine-2-carboxylate (2-pac) ligands and two water O atoms. The CuI atom has a triangular geometry, coordinated by one N atom and one C atom from two bridging cyanide ligands, and another N atom from the 2-pac ligand. The three-dimensional structure features a succession of two-dimensional sheets containing [Cu(CN)]n chains linked by Cu(2-pac)2(H2O)2 groups. The coordinated and free water molecules are involved in an extended three-dimensional hydrogen-bond network with the 2-pac ligands.