N-donation

The chemistry of technetium(II) and rhenium(II) is meagre and mainly confined to arsine and phosphine complexes. The best known of these are [MCl2(diars)2], obtained by reduction with hypophosphite and Sn respectively from the corresponding Tc and Re complexes, and in which the low oxidation state is presumably stabilized by n donation to the ligands. This oxidation state, however, is really best typified by manganese for which it is the most thoroughly studied and, in aqueous solution, by far the most... 

Fig. 8 Some tricyclic neutral hexacoordinated phosphorus derivatives with P-N donations...

Group (5) Acids that are a-acceptors but capable of n-donation in backbonding. This group includes cations with mobile d electrons e.g. Cu +, Co +, Fe"-". 

Mg2+ Carboxylate, phosphate and polyphosphate (total charge S= —2). N-donation (special)... 

The lack of secondary Te- -Cl interactions can be correlated with the presence of two aryl substituents with n-donating NMe2 groups. In an opposite way, electron-withdrawing fluorine atoms enhance the Lewis acidity of compounds (RF)2TeX2, leading to fluorine-bridged chains (with X=F) and related chain structures with X=C1 or Br.107... 

A low spin -dntermediate spin transition has also been found for a unique Fe(III) compound having an octahedral FeN4S2 environment [126]. In this compound the Fe(III) ion is surrounded by the tetradentate N-donating macrocycle AT,N/-dimethyl-2,ll-diaza[3.3](2,6)pyridinophane together with... 

The use of appropriate tetradentate N202-donating Schiff base ligands (Fig. 14) together with the incorporation of the N-donating nitrosyl anion has resulted in the formation of a unique series of five-coordinate Fe(III) spin crossover materials containing FeN302 chromophores. 

Nd YAG Q-switched laser, in fine art examination/ conservation, 11 413 N-donating ligands, complexation with uranium, 25 434-436 Near-edge X-ray absorption fine structure (NEXAFS), 24 72... 

Nitrogen (N), 17 270-289. See also N2 oxidation N-donating ligands Nitrogen compounds Nitrogen fixation Titanium-nitrogen compounds... 

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