Two one-dimensional chain-like cyanide-bridged compounds, [Fe(Phen)2(CN)2Ni(Cyclam)](ClO4)2·DMF-2H2O 1 (Cyclam = 1,4,8,11-tetraaza-cyclotetradecane, Phen = 1,10-phenanthroline, and DMF = N,N-dimethylform...Two one-dimensional chain-like cyanide-bridged compounds, [Fe(Phen)2(CN)2Ni(Cyclam)](ClO4)2·DMF-2H2O 1 (Cyclam = 1,4,8,11-tetraaza-cyclotetradecane, Phen = 1,10-phenanthroline, and DMF = N,N-dimethylformamide) and [Fe(Phen)2(CN)2Zn(Cyclam)](PF6)2·CH3CN 2, were prepared by the reaction of [Fe(Phen)2(CN)2]·2H2O with M(Cyclam)^2+ (M = Ni, Zn). In complexes 1 and 2, the metal atoms are connected alternatively with CN groups. X-ray structure and IR analyses for 1 and 2 were performed. Structure analysis revealed that both complexes are centrosymmetric and the geometry around each metal atom is an octahedron. The two complexes crystallize in triclinic with space group of P^1-. For 1, a = 10.439(4), b = 14.976(7), c = 15.914(8)A,α = 83.168(15), β = 74.338(15), γ = 78.023(15)°, V = 2338.3(18)A^3, Z = 2, Mr = 1035.37, Dc = 1.471 g/cm^3, F(000) = 1076,μ = 0.895 mm^-1, the final R = 0.0616 and wR = 0.1414 for 5849 observed reflections (1 〉 2σ(I)). For 2, a = 9.656(6), b = 15.404(9), c = 15.822(10)A, α = 78.68(2), β= 78.917(19), γ = 77.15(2)°, V = 2223(2)A^3, Z = 2, Mr = 1064.87, Dc = 1.587 g/cm^3, F(000) = 1078,μ = 1.032 mm^-1, the final R = 0.0672 and wR = 0.1595 for 6819 observed reflections (I 〉 2σ(I)).展开更多
The effect of sintering dispersed and bulk,low molecular weight(M_n=50,000 Da),nano-emulsionpolytetrafluoroethylene(PTFE)particles near their melting point is described.With the nascent particles consisting of ca.75 n...The effect of sintering dispersed and bulk,low molecular weight(M_n=50,000 Da),nano-emulsionpolytetrafluoroethylene(PTFE)particles near their melting point is described.With the nascent particles consisting of ca.75 nm diameter,hexagonal,single crystals,sintering at,e.g.,350℃,results,initially,in merger of neighboring particles,followed by individual molecular motion on the substrate and the formation of folded chain,lamellar single crystals andspherulites,and on-edge ribbons.It is suggested these structures develop,with time,in the mesomorphic“melt”.Sintering ofthe bulk resin yields extended chain,band structures,as well as folded chain lamellae;end-surface to end-surface merger,possibly by end-to-end polymerization,occurs with increasing time.展开更多
A new imidazolium compound, C15H17N4ClO4, was prepared from a flexible bidentate ligand of 1,3-di(imidazol-1-ylmethyl)-5-methylbenzene, and characterized by X-ray analysis. It is of orthorhombic, space group Pnma with...A new imidazolium compound, C15H17N4ClO4, was prepared from a flexible bidentate ligand of 1,3-di(imidazol-1-ylmethyl)-5-methylbenzene, and characterized by X-ray analysis. It is of orthorhombic, space group Pnma with a = 8.182(2), b = 12.874(3), c = 15.611(4) ? V = 1644.4(7) 3, Dc = 1.425 g/cm3, Z = 4, Mr = 352.78, m(MoKa) = 0.944 mm-1, F(000) = 736, S = 1.036, the final R = 0.0521 and wR = 0.1187 for 1128 observed reflections (I > 2s(I)). An infinite one-dimensional zigzag chain is formed by NH…N hydrogen bonding interactions between the imidazolium salt cations.展开更多
Two new isomorphous metal-organic coordination polymers, [Zn(dhmdb)(2,2'- bpy)]n 1 and [Zn(dhmdb)(1,10-phen)]n 2, have been obtained under hydrothermal reactions from 4,4'-(dihydroxymethylene)dibenzoic ac...Two new isomorphous metal-organic coordination polymers, [Zn(dhmdb)(2,2'- bpy)]n 1 and [Zn(dhmdb)(1,10-phen)]n 2, have been obtained under hydrothermal reactions from 4,4'-(dihydroxymethylene)dibenzoic acid (H2dhmdb), Zn(NO3)2·6H2O and 2,2'-pyridine or 1,10- phenanthroline, respectively. Compounds 1 and 2 have been characterized by FT-IR spectroscopy, thermal analysis and single-crystal X-ray diffraction. The zigzag chains of 1 and 2 are linked into three-dimensional supramolecular networks by both O–H…O hydrogen bonds and π…π stacking interactions. Crystal data for 1: ZnC25H18N2O6, Mr = 507.78, orthorhombic, space group Pbca, a = 14.031(3), b = 10.826(2), c = 27.343(6), V = 4153.5(14)3, Z = 8, Dc = 1.624 g/cm3, F(000) = 2080, μ = 1.231 mm-1, R = 0.0699 and wR = 0.1829. Crystal data for 2: ZnC27H18N2O6, Mr = 531.80, orthorhombic, space group Pbca, a = 13.796(3), b = 10.809(2), c = 28.612(6), V = 4266.8(15)3, Z = 8, Dc = 1.656 g/cm3, F(000) = 2176, μ = 1.203 mm-1, R = 0.0454 and wR = 0.1399.展开更多
The new ligand 2-((pyridin-4-ylmethyl)thio)-5-(quinoline-2-yl)-1,3,4-oxadiazole(L) and Ag Cl O4 produced a new coordination polymer: [(Ag2L2Cl O4)ClO 4]n(1). The complex has been characterized by single-c...The new ligand 2-((pyridin-4-ylmethyl)thio)-5-(quinoline-2-yl)-1,3,4-oxadiazole(L) and Ag Cl O4 produced a new coordination polymer: [(Ag2L2Cl O4)ClO 4]n(1). The complex has been characterized by single-crystal X-ray diffraction, IR, TGA, PXRD, UV and elemental analysis. Compound 1 crystallizes in triclinic system, space group P1, with a = 8.4593(5), b = 14.5903(9), c = 15.7908(10) A, α = 97.357(5), β = 99.116(5), γ = 104.470(5)°, V = 1834.43(20) A3, Dc = 1.91056 g/cm^3, Mr = 1055.38, Z = 2, F(000) = 1048, u = 1.399 mm-1, the final S = 1.002, R = 0.049 and wR = 0.105. The compound consists of a double helix chain. The neighboring chains interact via two kinds of π-π interactions to form a two-dimensional(2D) sheet. Each sheet interacts with the neighboring sheets via π-π interactions to form an extended 3D supramolecular network.展开更多
The title complex [Zn2(hfipbb)2(2,2′-bpy)2], 1 has been hydrothermally synthesized from Zn(NO3)2·6H2O, 4,4′-(hexafluoroisopropylidene)bis(benzoic acid) and 2,2′-bipyridine. Singlecrystal X-ray analys...The title complex [Zn2(hfipbb)2(2,2′-bpy)2], 1 has been hydrothermally synthesized from Zn(NO3)2·6H2O, 4,4′-(hexafluoroisopropylidene)bis(benzoic acid) and 2,2′-bipyridine. Singlecrystal X-ray analysis reveals that 1 presents a one-dimensional coordination polymer with pseudo-helical chain structure. Two Zn(Ⅱ) atoms in an unsymmetrical unit of 1 adopt distorted octahedral and square-pyramidal coordination geometries, respectively. The packing of parallel chains gives a three-dimensional supramolecular network supported by π-π stacking interactions. Crystal data: C54H32F12N4O8Zn2, Mr = 1223.58, monoclinic, space group P2 1/c, a = 27.557(6), b = 16.751(3), c = 11.350(2) A, β= 99.21(3)°, V= 5171.5(18) A^3, Z= 4, Dc = 1.572 g/cm^3, F(000) = 2464, μ= 1.030 mm^-1, the final R = 0.0552 and wR = 0.1070 for 6631 observed reflections (I〉 2σ(I)).展开更多
It is believed that gel spun polyethylene(PE)fibers have a somewhat extended chain crystalstructure,because of the disentangling of the chains which takes place in semi-dilute solutionand the ultra high draw ratio use...It is believed that gel spun polyethylene(PE)fibers have a somewhat extended chain crystalstructure,because of the disentangling of the chains which takes place in semi-dilute solutionand the ultra high draw ratio used.Ten years ago,PE shish-kebabs grown from dilute solutionwere proved to have extended chain backbone which causes the raising of its melting point.These crystals were found to have a triclinic crystal phase,This study shows a different result forgel spun ultra high drawn PE fiber.The unit cell remains orthorhombic even if the draw ratioreaches 50;as the draw ratio increases,the length in a and b axes are shortened while that in c ax-is changes quite insignificantly.When the draw ratio is over 10,two endothermic melting peakscan be seen in the DSC curves with corresponding peak temperature of 136.7-145.3℃.The lat-ter peak is attributed to the amount of extended chain crystal.展开更多
The title complex, [Mn3(μ-oxalate)3(μ-4,4′-bpy)2(4,4′-bpy)2]n, was synthesized and structurally characterized by X-ray crystallography. It crystallizes in the monoclinic, space group P2 1/c with a = 16.3222...The title complex, [Mn3(μ-oxalate)3(μ-4,4′-bpy)2(4,4′-bpy)2]n, was synthesized and structurally characterized by X-ray crystallography. It crystallizes in the monoclinic, space group P2 1/c with a = 16.3222(6), b = 16.2594(5), c = 16.4885(5) A, β = 94.9900(10)°, V= 4359.3(2) A^3, Z = 4, Mn3C46N8O12H32, Mr = 1053.62, Dc = 1.605 g/cm^3, F(000) = 2140 and μ(MoKa) = 0.932 mm^-1. The structure was refined to R = 0.0578 and wR = 0.1061 for 4795 observed reflections (I 〉 2σ(I)). The oxalate anions behave as the bridging ligand and link two manganese atoms repeatedly to form infinite one-dimensional chains which further extend into a two-dimensional network by bridging 4,4′-bpy ligands.展开更多
基金the grants from 973 Program (2007CB815301 and 2006CB932904)the National Natural Science Foundation of China (20333070 and 20673118)+1 种基金the Science Foundation of CAS (KJCX2-YW-M05)Fujian Province (2006L2005, 2006F3132 and 2007J0171)
文摘Two one-dimensional chain-like cyanide-bridged compounds, [Fe(Phen)2(CN)2Ni(Cyclam)](ClO4)2·DMF-2H2O 1 (Cyclam = 1,4,8,11-tetraaza-cyclotetradecane, Phen = 1,10-phenanthroline, and DMF = N,N-dimethylformamide) and [Fe(Phen)2(CN)2Zn(Cyclam)](PF6)2·CH3CN 2, were prepared by the reaction of [Fe(Phen)2(CN)2]·2H2O with M(Cyclam)^2+ (M = Ni, Zn). In complexes 1 and 2, the metal atoms are connected alternatively with CN groups. X-ray structure and IR analyses for 1 and 2 were performed. Structure analysis revealed that both complexes are centrosymmetric and the geometry around each metal atom is an octahedron. The two complexes crystallize in triclinic with space group of P^1-. For 1, a = 10.439(4), b = 14.976(7), c = 15.914(8)A,α = 83.168(15), β = 74.338(15), γ = 78.023(15)°, V = 2338.3(18)A^3, Z = 2, Mr = 1035.37, Dc = 1.471 g/cm^3, F(000) = 1076,μ = 0.895 mm^-1, the final R = 0.0616 and wR = 0.1414 for 5849 observed reflections (1 〉 2σ(I)). For 2, a = 9.656(6), b = 15.404(9), c = 15.822(10)A, α = 78.68(2), β= 78.917(19), γ = 77.15(2)°, V = 2223(2)A^3, Z = 2, Mr = 1064.87, Dc = 1.587 g/cm^3, F(000) = 1078,μ = 1.032 mm^-1, the final R = 0.0672 and wR = 0.1595 for 6819 observed reflections (I 〉 2σ(I)).
文摘The effect of sintering dispersed and bulk,low molecular weight(M_n=50,000 Da),nano-emulsionpolytetrafluoroethylene(PTFE)particles near their melting point is described.With the nascent particles consisting of ca.75 nm diameter,hexagonal,single crystals,sintering at,e.g.,350℃,results,initially,in merger of neighboring particles,followed by individual molecular motion on the substrate and the formation of folded chain,lamellar single crystals andspherulites,and on-edge ribbons.It is suggested these structures develop,with time,in the mesomorphic“melt”.Sintering ofthe bulk resin yields extended chain,band structures,as well as folded chain lamellae;end-surface to end-surface merger,possibly by end-to-end polymerization,occurs with increasing time.
基金the Natural Science Foundation of Jiangsu province (Grant No Bk2001031)
文摘A new imidazolium compound, C15H17N4ClO4, was prepared from a flexible bidentate ligand of 1,3-di(imidazol-1-ylmethyl)-5-methylbenzene, and characterized by X-ray analysis. It is of orthorhombic, space group Pnma with a = 8.182(2), b = 12.874(3), c = 15.611(4) ? V = 1644.4(7) 3, Dc = 1.425 g/cm3, Z = 4, Mr = 352.78, m(MoKa) = 0.944 mm-1, F(000) = 736, S = 1.036, the final R = 0.0521 and wR = 0.1187 for 1128 observed reflections (I > 2s(I)). An infinite one-dimensional zigzag chain is formed by NH…N hydrogen bonding interactions between the imidazolium salt cations.
基金supported by the National Natural Science Foundation of China(21071087,91122012)the Open Foundation of State Key Laboratory of Structural Chemistry(20090057)the K.C.Wong Magna Fund in Ningbo University
文摘Two new isomorphous metal-organic coordination polymers, [Zn(dhmdb)(2,2'- bpy)]n 1 and [Zn(dhmdb)(1,10-phen)]n 2, have been obtained under hydrothermal reactions from 4,4'-(dihydroxymethylene)dibenzoic acid (H2dhmdb), Zn(NO3)2·6H2O and 2,2'-pyridine or 1,10- phenanthroline, respectively. Compounds 1 and 2 have been characterized by FT-IR spectroscopy, thermal analysis and single-crystal X-ray diffraction. The zigzag chains of 1 and 2 are linked into three-dimensional supramolecular networks by both O–H…O hydrogen bonds and π…π stacking interactions. Crystal data for 1: ZnC25H18N2O6, Mr = 507.78, orthorhombic, space group Pbca, a = 14.031(3), b = 10.826(2), c = 27.343(6), V = 4153.5(14)3, Z = 8, Dc = 1.624 g/cm3, F(000) = 2080, μ = 1.231 mm-1, R = 0.0699 and wR = 0.1829. Crystal data for 2: ZnC27H18N2O6, Mr = 531.80, orthorhombic, space group Pbca, a = 13.796(3), b = 10.809(2), c = 28.612(6), V = 4266.8(15)3, Z = 8, Dc = 1.656 g/cm3, F(000) = 2176, μ = 1.203 mm-1, R = 0.0454 and wR = 0.1399.
基金financially supported by the National Natural Science Foundation of China(No.21201112)
文摘The new ligand 2-((pyridin-4-ylmethyl)thio)-5-(quinoline-2-yl)-1,3,4-oxadiazole(L) and Ag Cl O4 produced a new coordination polymer: [(Ag2L2Cl O4)ClO 4]n(1). The complex has been characterized by single-crystal X-ray diffraction, IR, TGA, PXRD, UV and elemental analysis. Compound 1 crystallizes in triclinic system, space group P1, with a = 8.4593(5), b = 14.5903(9), c = 15.7908(10) A, α = 97.357(5), β = 99.116(5), γ = 104.470(5)°, V = 1834.43(20) A3, Dc = 1.91056 g/cm^3, Mr = 1055.38, Z = 2, F(000) = 1048, u = 1.399 mm-1, the final S = 1.002, R = 0.049 and wR = 0.105. The compound consists of a double helix chain. The neighboring chains interact via two kinds of π-π interactions to form a two-dimensional(2D) sheet. Each sheet interacts with the neighboring sheets via π-π interactions to form an extended 3D supramolecular network.
基金Supported by the National Natural Science Foundation of China (20701022)Natural Science Foundation of Zhejiang Province (Y4080435)+1 种基金Natural Science Foundation of Ningbo Municipal (2007A610024, 2008A610045)Open Foundation of Ningbo Municipal Key Laboratory (2007A22003)
文摘The title complex [Zn2(hfipbb)2(2,2′-bpy)2], 1 has been hydrothermally synthesized from Zn(NO3)2·6H2O, 4,4′-(hexafluoroisopropylidene)bis(benzoic acid) and 2,2′-bipyridine. Singlecrystal X-ray analysis reveals that 1 presents a one-dimensional coordination polymer with pseudo-helical chain structure. Two Zn(Ⅱ) atoms in an unsymmetrical unit of 1 adopt distorted octahedral and square-pyramidal coordination geometries, respectively. The packing of parallel chains gives a three-dimensional supramolecular network supported by π-π stacking interactions. Crystal data: C54H32F12N4O8Zn2, Mr = 1223.58, monoclinic, space group P2 1/c, a = 27.557(6), b = 16.751(3), c = 11.350(2) A, β= 99.21(3)°, V= 5171.5(18) A^3, Z= 4, Dc = 1.572 g/cm^3, F(000) = 2464, μ= 1.030 mm^-1, the final R = 0.0552 and wR = 0.1070 for 6631 observed reflections (I〉 2σ(I)).
基金This project is supported by National Science Foundation of China
文摘It is believed that gel spun polyethylene(PE)fibers have a somewhat extended chain crystalstructure,because of the disentangling of the chains which takes place in semi-dilute solutionand the ultra high draw ratio used.Ten years ago,PE shish-kebabs grown from dilute solutionwere proved to have extended chain backbone which causes the raising of its melting point.These crystals were found to have a triclinic crystal phase,This study shows a different result forgel spun ultra high drawn PE fiber.The unit cell remains orthorhombic even if the draw ratioreaches 50;as the draw ratio increases,the length in a and b axes are shortened while that in c ax-is changes quite insignificantly.When the draw ratio is over 10,two endothermic melting peakscan be seen in the DSC curves with corresponding peak temperature of 136.7-145.3℃.The lat-ter peak is attributed to the amount of extended chain crystal.
文摘The title complex, [Mn3(μ-oxalate)3(μ-4,4′-bpy)2(4,4′-bpy)2]n, was synthesized and structurally characterized by X-ray crystallography. It crystallizes in the monoclinic, space group P2 1/c with a = 16.3222(6), b = 16.2594(5), c = 16.4885(5) A, β = 94.9900(10)°, V= 4359.3(2) A^3, Z = 4, Mn3C46N8O12H32, Mr = 1053.62, Dc = 1.605 g/cm^3, F(000) = 2140 and μ(MoKa) = 0.932 mm^-1. The structure was refined to R = 0.0578 and wR = 0.1061 for 4795 observed reflections (I 〉 2σ(I)). The oxalate anions behave as the bridging ligand and link two manganese atoms repeatedly to form infinite one-dimensional chains which further extend into a two-dimensional network by bridging 4,4′-bpy ligands.