Heterogene Reaktionen fester Nickel (II)‐Komplexe, XIII. Stereochemische Veränderungen in Isothiocyanato‐Nickel(II)‐Komplexen mit Dialkylpyridinen bei thermischen Zersetzungs‐reaktionen

1988

The paper deals with the chemical and physical factors influencing the thermal octahedral square planar changes of nickel(II) complexes in the solid phase. The relationship between these transformations and the tetragonal distortion of the octahedral ligand field is discussed. Depending on the coordination of the ligands, these transformations can be divided into two groups: octahedral monomer ~-, square planar monomer, and octahedral polymer ~ square planar monomer changes. Attention is directed only to octahedral and square planar Ni(II) complexes (square planar complexes with chromophores [NiN,], [NiN202] and [NiO,]), which can be isolated in the solid state before and after heating. The possibility of such a configurational change seems to be dependent upon the thermal stabilities of the initial and final complexes, the electronic and steric properties of the ligands, the complexing ability of the central atom, and particularly the equatorial-axial interactions of the ligands via the central atom.

Section: X2nhzomentioning

confidence: 81%

“…Similar observations have been made with the ligands R~O--CH2--CO C(CH3) 3 [28], where R is p-tolyl, panisyl, p-chlorobenzyl, p-bromobenzyl or p-nitrobenzyl. When Y = Br, thermal decomposition occurs in the following way [31]: Table 6 [32][33][34][35]. (tmen = N,N,N,N-tetramethylethylenediamine, ion, Y = I, C104).…”

Section: X2nhzomentioning

confidence: 99%

Thermal properties of solid nickel(II) coordination compounds

1988

“…Similarly, one band was observed in the mentioned region for nickel(ll) complexes with lutidine [6], quinoline [7] and lepidine [8]. I R-spectra, cm-1 9 sh -shoulder, br --broad; 9 the obtained amount of sample was not sufficient for a precise measurement of ~-eff; 9 overlaid by 2-NH2py absorption assigned to ligands.…”

Section: Maxima Of Absorption Bandsmentioning

confidence: 92%

Heterogeneous reactions of solid nickel(II) complexes. XVIII

Jamnický

1983

The stoichiometry of thermal decomposition was studied for the following compounds:Ni(NCS)2(2-Mepy) 2 (I), (Me --methyl, py --pyridine), Ni(NCS)2(2-Etpy) 2(11) (Et=ethyl),The release of volatile ligands 2-Rpy is a one-step process for complexes I, II, III and IV, while for V and VI it is a two-step process, Ni(NCS)2(2-NH2py) ! (VII) being formed as an intermediate complex. It was found that complexes I and I I are square-planar; the others exhibited pseudo-octahedral geometry. The differences in stereochemistry of the above complexes are explained by the different electronic properties of 2-Rpy.

“…The investigated complexes undergo a one-step or two-step decomposition and for some of them square planar ~ octahedral changes take place [35]. The investigated complexes undergo a one-step or two-step decomposition and for some of them square planar ~ octahedral changes take place [35].…”

Section: A) Study Of Factors Affecting Square Pianar --* Octahedral Cmentioning

confidence: 99%

Thermal properties of solid nickel(II) coordination compounds

Šramko

Gažo

1979

The paper deals with the chemical and physical factors influencing the stoichiometry of thermal decomposition of solid coordination compounds. Nickel(II) coordination compounds were used as examples : the problem of the relationship between the structure of the initial compound (and of its intermediates) and the stoichiometry of thermal decomposition is discussed; experimental conditions are shown to affect this decomposition, and the conceptions of the apparent and real stoichiometries of thermal decomposition are discussed. The results obtained may have a more general meaning.