83864-14-6Relevant articles and documents
Thermal and structural studies of amide complexes of transition metal(II) chlorides. II: Kinetics
Nelwamondo, Aubrey N.,Eve, Desmond J.,Brown, Michael E.
, p. 177 - 186 (1998)
The possibility of correlating the kinetic parameters for the thermal decompositions of a series of NiLCl2 complexes, where L=N-methylformamide (nmf), N-methylacetamide (nma) or acetamide (aa), with the nature (steric and electronic effects) of the coordinated ligands and the strengths of the metal-ligand bonds has been explored. The rates of removal of L in single endothermic processes were measured using isothermal TG in nitrogen. Plots of α against time are deceleratory and are best described by either the R2 or R3 expressions. An empirical (B2) expression: vr=1-(kt)b, was introduced to give the best description of the results for the Ni(nma)Cl2 complex. Comparable Ea values were obtained using various isothermal and non-isothermal methods of analysis. Ea values for the NiLCl2 system (calculated using the R3 model) generally increased with an increase in basicity of the amide ligand:N-methylformamide~acetamidea values were found to be lower than the corresponding decomposition enthalpies (ΔHL), indicating that cleavage of the nickel-amide bond could be the rate-controlling event. The order of Ea values was found not to coincide with that of the ΔHL values. Extrapolated onset temperatures (Te) and temperatures at maximum decomposition rate (Tmax) were determined from TG and DSC curves. No simple correlation was found between Ea, ΔHL, Te or Tmax and the spectral properties of the complexes.
Non-isothermal kinetic and thermodynamic study for the dehydration of copper(II) chloride dihydrate and nickel chloride hexahydrate
Mohamed, M. A.,Halawy, S. A.
, p. 147 - 160 (1994)
Non-isothermal dehydration of copper chloride dihydrate and nickel chloride hexahydrate were studied by using TG, DTG, DTA and DSC measurements. The copper chloride salt loses its two water molecules in one step while nickel chloride salt dehydrates in three consecutive steps. The first two steps involve the loss of 4 water molecules in two overlapped steps while the third step involves the dehydration of the dihydrate salt to give the anhydrous NiCl2. Activation energies (ΔE) and the frequency factor (A) were calculated from DTG and DTA results. We have also calculated the different thermodynamic parameters, e.g. enthalpy change (ΔH), heat capacity (Cp) and the entropy change (ΔS) from DSC measurements for both reactants. The isothermal rehydration of the completely dehydrated salts was studied in air and under saturated vapour pressure of water. Anhydrous nickel chloride was found to rehydrate in three consecutive steps while the copper salt rehydrated in one step.
A co-reduction-silicification route to δ-Ni2Si nanowire
Yang, Baojun,Hu, Hanmei,Wu, Yucheng,Luo, Tao,Yang, Xiaogang,Qian, Yitai
, p. 326 - 327 (2005)
δ-Ni2Si nanowires have been synthesized via a co-reduction-silicification route, using anhydrous NiCl2 and SiCl4 as nickel source and silicon source, respectively, and metallic Na as reductant in an autoclave at 600°C for 16 h. Transmission electron microscopy (TEM) observations show that the diameters of nanowires ranged in 10-100 nm and lengths up to several tens micrometers. The possible formation mechanism is discussed. Copyright
Covalent embedding of Ni2+/Fe3+ cyanometallate structures in silica by sol-gel processing
Felbermair, Elisabeth,Sidorenko, Andrey,Paschen, Silke,Akbarzadeh, Johanna,Peterlik, Herwig,Schubert, Ulrich
, p. 9212 - 9215 (2014)
Compound [Ni(AEAPTS)2]3[Fe(CN)6] 2 (AEAPTS=N-(2-aminoethyl)-3-aminopropyltrimethoxysilane), in which Ni2+ and Fe3+ ions are ferromagnetically coupled through cyano bridges, was prepared. Sol-gel processing of the AEAPTS derivative resulted in incorporation of the cyanometallate in silica. The obtained material is magnetically ordered below 22 K with an effective magnetic moment μeff of 4.46 μB at room temperature, a maximum of 8.60 μB at approximately 15 K and a narrow hysteresis at 2 K, with a saturation remanence of about 300 emu mol-1 and a coercitivity of 0.03 T. Magnetic crowd: [Ni(AEAPTS)2]3[Fe(CN) 6]2 (AEAPTS = N-(2-aminoethyl)-3- aminopropyltrimethoxysilane) was covalently tethered to silica gel. The obtained material is magnetically ordered below 22 K with an effective magnetic moment μeff of 4.46 μB at room temperature, a maximum of 8.60 μB at approximately 15 K, and a narrow hysteresis at 2 K (saturation remanence≈300 emu mol-1, coercitivity 0.03 T).
Reactivity of ammonium chloride/mercuric chloride mixtures with monel containers. The new compounds (NH4)2(NH3)x[Ni(NH3) 2Cl4] and (NH4)5Cl2[CuCl2] [CuCl4]
Meyer, Gerd,Nockemann, Peter
, p. 254 - 259 (2001)
Ammonium chloride/mercuric chloride mixtures (molar ratio 2:1) react at 350°C with Monel (Cu68Ni32) to yield (NH4)NiCl3 and mercury and copper amalgam, respectively. With larger amounts of (NH4)Cl in the reaction mixture, dark green (NH4)2(NH3)x[Ni(NH3) 2Cl4] (x ≈ 0.77) (1) is also formed as a main product. Light blue crystals of the mixed-valent copper(I,II) chloride (NH4)5Cl2[CuCl2] [CuCl4] (2) were obtained as a minor byproduct from a 4:1 reaction mixture. The crystal structures were determined from single crystal X-ray data; (1): tetragonal, I4/mmm, a = 770.9(1), c = 794.2(2) pm, 190 reflections, R1 = 0.0263; (2): tetragonal, I4/mcm, a = 874.8(1), c = 2329.2(3) pm, 451 reflections, R1 = 0.0736. In (1) Ni2+ resides in trans-[Ni(NH3)2Cl4]2- octahedra, and in (2) copper(I) is linearly two-coordinated in [CuCl2]- and copper(II) resides in a flattened tetrahedron [CuCl4]2- with a tetrahedricity of 89%.
An analysis of the electronic spectra of some nickel(II) halide amine complexes
Lever,Nelson,Shepherd
, p. 810 - 813 (1965)
The diffuse reflectance spectra (30,000-10,000 cm.-1) of 28 six-coordinate nickel(II) complexes of microsymmetry NiN2X (N = amine, X = Cl or Br) are analyzed in terms of octahedral stereochemistry. It is shown that the rule of averag
Standard enthalpy of formation of Cl2(cr) as determined by solution-reaction calorimetry
Kuriyama, Nobuhiro,Sakiyama, Minoru
, p. 729 - 734 (1988)
The standard molar enthalpy at 298.15 K was determined by solution-reaction calorimetry for the reaction: NiCl2(cr) + 6NH4Cl(cr) = Cl2(cr) + 6HCl(g).From the standard molar enthalpy of reaction, the standard molar enthalpy of formation of Cl2(cr) was derived.The derived value is in reasonably good agreement with a value given in the NBS tables of chemical thermodynamic properties, which was based on the analysis of the equilibria: NiCl2(cr) + NH3(g) = Cl2(cr), Cl2(cr) + NH3(g) = Cl2(cr), and Cl2(cr) + 4NH3(g) = Cl2(cr).
X-ray study of Kr and Xe adsorbed on the basal plane of nickel chloride
Morishige, K.,Hanayama, M.,Kittaka, S.
, p. 451 - 456 (1988)
X-ray scattering has been used to investigate the structure and phase transitions of Xe and Kr films adsorbed on the basal plane of NiCl2.The x-ray scattering measurements were carried out both as a function of temperature at fixed coverage and as a function of coverage at fixed temperature in the monolayer and bilayer coverage regimes.The results indicate that both the monolayers of Xe and Kr adsorbed on the basal plane of NiCl2 form a 2D solid of the simple triangular structure incommensurate with the substrate and 2D melting is first order in the incommensurate solid of Xe but continuous in that of Kr.With tha addition of the second-layers atoms the interparticle distance of the adsorbed atoms reduces and the crystallinity of the incommensurate solid improves.
X-ray diffraction, spectral and magnetic studies of the nickel(II) thiocyanate complexes with tridentate 2,6-dithiocarboxamidopyridine SNS and 2,6-dicarboxamidopyridine ONO ligands: Influence of donor atoms on the coordination geometry of nickel
Kapoor, Ramesh,Kataria, Ashok,Pathak, Anuradha,Venugopalan, Paloth,Hundal, Geeta,Kapoor, Pratibha
, p. 1221 - 1231 (2005)
The systematic investigation of electronic effects on the coordination geometry of nickel(II) thiocyanate complexes with the tridentate N,N,N′,N′-tetraethylpyridine-2,6-dithiocarboxamide (S-dept) and N,N,N′,N′-tetraethylpyridine-2,6-dicarboxamide (O-deap) ligands shows a significant change in the geometry of the metallic site. Their complexes conform to composition [Ni2(μ-NCS)2(S-dept) 2(NCS)2] (1), [Ni(NCS)2(O-deap)(CH 3CN)] ? CH3CN (2) and [Ni(NCS)2(O-deap) (C2H5OH)] (3), respectively. X-ray crystallographic studies were done for 1-3. In the crystal lattice, complex 1 exists as a centrosymmetric dimer in which the dinuclear core is bridged by two N-bonded thiocyanate groups. The near octahedral geometry of the nickel atom is achieved through the two bridging N atoms of the thiocyanate groups, three SNS donor atoms of the ligand S-dept and through the terminal nitrogen atom of a non-bridging thiocyanate moiety. To the best of our knowledge, complex 1 presents the first example in literature with the highest asymmetry in N-bridging thiocyanato ligands. Ni ion is coordinated to ONO donor set of atoms of O-deap and two N-bonded NCS terminal groups. The sixth coordination site is completed by the N atom of an acetonitrile molecule. The coordination around Ni atom in 3 is also distorted octahedral. The change in the sixth coordination position from acetonitrile in 2 to ethanol in 3 has a profound influence in the overall topology of the metal-ligand complex. The complex interplay of weak interactions in stabilizing the 3-dimensional lattice of these molecules is well demonstrated.
Anodic Dissolution of Nickel Sulfide in Acidic Cu(II) Electrolytes
Natorkhin
, p. 51 - 54 (2001)
The effect of ligands on the anodic dissolution of NiS in copper-containing acidic electrolytes was studied.
