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1.
The complex [Ni(tn)2{N(CN)2}]ClO4 (tn=trimethylenediamine) has been synthesized and the structure has been determined. The complex forms a one-dimensional chain structure via the bidentate bridging ligand dicyanamide. A two-dimensional networks is formed via interchain hydrogen bond interactions.  相似文献   
2.
The nickel(II) complex [Ni(en)2{N(CN)2}]ClO4 1 (en?=?ethylenediamine) has been synthesized and its structure determined. The complex forms a one-dimensional chain structure via the bidentate bridging ligand dicyanamide. A two-dimensional network is formed via interchain hydrogen-bond interactions. The magnetic properties of the compound (5–300?K) show the existence of weak antiferromagnetic exchange interactions between paramagnetic centers along chains.  相似文献   
3.
In this study the synthesis, crystal structure and characterization of three new transition metal polynuclear compounds with formula [Cu(dipm)(μ-dca)2]n(H2O) (1), [Ni(dipm)(μ-dca)2]n(C2H6O)1/2 (2) and [Cd(dipm)(μ-dca)2]n (3) (in which dipm = bis(pyrimidin-2-yl)amine and dca = dicyanamide) are reported. The isostructural compounds 1 and 2 contain a double-bridging end-to-end dca unit connecting two metal ions and a single bridging end-to-end dca unit between subsequent metals. Compound 3 exhibits only single bridging end-to-end dca units, oriented in three directions, giving rise to a 3D framework.  相似文献   
4.
Summary New dicyanamide complexes of the typeM[N(CN)2]2 L 2 (M=Cu or Ni;L=2-, 3-, 4-aminopyridine, 2-amino-5-nitropyridine) and Co[N(CN)2]2 (2-amino-5-nitropyridine)2 were prepared and studied by spectroscopic methods as well as by room-temperature magnetic moments. The results show that the Cu(II) complexes have elongated pseudooctahedral structures while the Ni(II) and Co(II) complexes are octahedral. In most cases the N(CN)2 groups are in bridging function and through their cyanide nitrogens, or-more rarely-amide and cyanide nitrogens connect the basic structure units into polymeric conglomerates. In the Cu(II) systems exchange coupling is seen from the eff value or ESR spectrum.
Professor Viktor Gutmann zum 70. Geburtstag gewidmet  相似文献   
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6.
The new cadmium(II) coordination polymer [Cd(bte)2(dca)2]n 1 (bte = 1,2-bis(1,2,4- triazol-1-yl)ethane, dca = dicyanamide) was synthesized and characterized by single-crystal X-ray diffraction. The crystal is of monoclinic, space group P21/n with a = 8.7148(15), b = 8.6142(17), c = 15.204(3) A, β = 92.100(10)o, V = 1140.6(4) A3, Z = 2, Mr = 572.87, Dc = 1.668 g/cm3, F(000) = 572, μ = 1.004 mm-1, the final R = 0.0654 and wR = 0.1429 for 1737 observed reflections (I > 2σ(I)). The cadmium atom is coordinated equatorially by four nitrogen atoms from four bte ligands and axially by two nitrogen atoms from two dca anions to adopt a distorted octahedral geometry. Each bte molecule bridges two cadmium(II) atoms. Two strands of bte molecules are wrapped around each other, and held together by cadmium(II) atoms. 1 Forms a double chain structure containing eighteen-membered Cd2(bte)2 rings.  相似文献   
7.
Magnesium dicyanamide tetrahydrate Mg[N(CN)2]2 · 4 H2O was synthesized by aqueous ion exchange starting from Na[N(CN)2] and Mg(NO3)2 · 6 H2O. The crystal structure was solved and refined on the basis of powder X‐ray diffraction data (P21/c, Z = 2, a = 737.50(2), b = 732.17(1), c = 971.67(2) pm, β = 98.074(1)°, wRp = 0.059, Rp = 0.046, RF = 0.075). In the crystal there are neutral complexes [Mg[N(CN)2]2(H2O)4] which are only connected via hydrogen bonds. Above 40 °C the tetrahydrate decomposes into anhydrous Mg[N(CN)2]2.  相似文献   
8.
A novel two‐dimensional cobalt complex, [Co(btrm)2(dca)]ClO4 ( 1 , btrm = 1,2‐bis(1,2,4‐triazole‐1‐yl)methane, dca = dicyanamide), was synthesized and characterized. X‐ray diffraction analyses reveal that the title complex crystallizes in the monoclinic space group C2/m with a = 29.507(13)Å, b = 17.804(8) Å, c = 14.709(7) Å, β = 119.916(7)°, Z = 12, and R1 = 0.0784, wR2 = 0.2041. The cobalt atom involves a six‐coordinated CoN6 environment, with a distorted octahedral coordination. Two btrm ligands connect the CoII atoms with the exodentate nitrogen atoms on the 4‐position of triazole rings to form a sixteen‐membered rhombic grid. The unprecedented double btrm bridges and μ1,5‐dca bridge connect the cobalt atoms to form a two‐dimensional grid‐like layered structure. The spectroscopic and magnetic properties have also been investigated.  相似文献   
9.
The synthesis, structure, and magnetic properties of four 2,2′‐dipyridylamine ligand (abbreviated as Hdpa) containing copper(II) complexes. There is one binuclear compound, which is [Cu21,1‐NCO)2(NCO)2(Hdpa)2] ( 1 ), and three mononuclear compounds, which are [Cu{N(CN)2}2(Hdpa)2] ( 2 ), [Cu(CH3CO2)(Hdpa)2·N(CN)2] ( 3 ), and [Cu(NCS)(Acac)] ( 4 ). Compounds 1 and 4 crystallize in the monoclinic system, space group P2(1)/c and Z = 4, with a = 8.2465(6) Å, b = 9.3059(7) Å, c = 16.0817(12) Å, β = 91.090(1)°, and V = 1233.90(16) Å3 for 1 and a = 7.6766(6) Å, b = 21.888(3) Å, c = 10.4678(12) Å, β = 90.301(2)°, and V= 1758.8(4) Å3 for 4 . Compounds 2 and 3 crystallize in the triclinic system, space group P‐1 and Z = 1, with a = 8.1140(3) Å, b = 8.2470(3) Å, c = 9.3120(4) Å, β = 102.2370(10)°, and V = 592.63(4) Å3 for 2 and a = 7.4780(2) Å, b = 12.5700(3) Å, c = 13.0450(3) Å, β = 96.351(2)°, and V = 1211.17(5) Å3 for 3 . Complex ( 1 ), the magnetic data was fitted by the Bleaney‐Bowers equation (1). A very good fit was derived with J = 23.96, Θ = ?1.5 (g = 1.97). Complex ( 1 ) shows the ferromagnetism. Complexes ( 2 ), ( 3 ) and ( 4 ) of have the it is the typical paramagnetic behavior of unpaired electrons. Under a low temperature around 25 K, complexes ( 2 ) and ( 3 ) show weak ferromagnetic behavior. They are the cause of hydrogen bonds.  相似文献   
10.
Preparation and Crystal Structures of Dicyanamido(triphenylphosphane)gold(I) and Nitrosodicyanomethanido(triphenylphosphane)gold(I) The coordination compounds [(Ph3P)Au{N(CN)2}] ( 1 ) and [(Ph3P)Au{ONC(CN)2}] ( 2 ) are obtained by the reaction of [Au(PPh3)]NO3 with Na[N(CN)2] or K[ONC(CN)2] in CH2Cl2. The compounds are characterized by IR spectroscopy and by crystal structure determination. 1 crystallizes triclinic in the space group P 1 with a = 930.16(4), b = 1011.89(13), c = 1118.35(16) pm, α = 115.327(10), β = 90.899(8), γ = 103.394(8)°, Z = 2. 2 crystallizes monoclinic in the space group P21/n with a = 832.59(10), b = 1139.30(16), c = 2078.9(4) pm, β = 99.84(2)°, Z = 4. The crystal structures of both compounds are built up by pairs of antiparallel oriented molecules with linear coordinated gold atoms and weak intermolecular Au–N‐interactions.  相似文献   
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