The thermal decomposition of metal complexes—II Some ammine and ethylenediamine complexes of nickel (II)

Thermolysis of some transition metal nitrate complexes with 1,4-diamino butane ligand

“…Corresponding metal oxides were obtained as final decomposition products at the end of thermal reactions. Such observation has also been made earlier during thermal studies of amine complexes of copper(II) nitrate [29,26], nickel(II) nitrate [26,38,39] and bis(ethylenediamine) metal perchlorate complexes [29].…”

Facile Uptake and Release of Ammonia by Nickel Halide Ammines

“…At 15 and 20 Kmin À1 ,t he rate of the diammine decomposition becomes comparable to that of the monoammine, and the complete three-step decompositionm echanism is, therefore, observed. These observations concur with the three-step mechanism observed by George and Wendtland [36] under heating at rates above 5Kmin À1 .H ence, overall one can conclude that the de-ammoniation of [Ni(NH 3 ) 6 ]X 2 for X = Cl follows the three-step process shown in Equations 1-3.…”

“…Several studies have examined the thermal desorptiono f one or more of the nickel hexaammines previously butr esults have been apparently contradictory in terms of the number and nature of decomposition steps observed. [24,35,36] Further,a lthought he structures of the diamminesN i(NH 3 ) 2 X 2 (X = Cl, Br) have been reported,t he detailso ft he changes in phase/structure with temperature for the NiX 2 -NH 3 systems are not comprehensive andt he structure of the iodide diammine remains as yet uncharacterised. [37] Thermogravimetric and differential thermala nalysisw ith mass spectrometry (TG-DTA-MS) with ah eating rateo f5Kmin À1 (Figure4) From the TG profiles,a mmonia releasea ppears to proceed in two steps.…”

From Al2O3-supported Ni(II)-ethylenediamine Complexes to CO Hydrogenation Catalysts: Importance of the Hydrogen Post-treatment Evidenced by XPS

“…Exposure to air certainly contributes to this oxidation, but it can be noted that once nickel particles have been reduced, the extent of their oxidation is lesser than before post-treatment. It is thus likely that an oxidic fraction is formed upon precursor decomposition, in line with the behaviour of the unsupported salts [20].…”