Dinitrogen splitting

Because of the different nature of those transitions, different photochemical products are formed depending on the excitation wavelength. Excitation into the inter-valence transition at 700 nm does not initiate any photoreactivity. However, irradiation with light <450 nm populates an MLCT state, resulting in transient oxidation of the metal centre, reduction of the N2 molecule, and dinitrogen splitting, with quantum yields 0.002 and 0.003 under 254 nm or 365 nm irradiation respectively. 

Scheme 44 Proposed mechanism for the photoinduced dinitrogen splitting in [ (Mes)3Mo 2()i-N2)]. ...

Klopsch I, Finger M, Wiirtele C, Milde B, Werz DB, Schneider S. Dinitrogen splitting and functionalization in the coordination sphere of rhenium. J Am Chem Soc. 2014 136 6881-6883. 

Splitting of dinitrogen to form nitrido (N1 2 3- 4 5) complexes on a three-coordinate molybdenum(III) complex (process described below)33... 

They, in contrast to Kishi and Roberts (52) and Johnson and Roberts (55), interpret the N(ls) peak at 405 eV as a satellite of the 400-eV peak moreover Fuggle and Menzel observe two components to the 400-eV peak, one at 399.1 eV and the other at 400.4 eV. These they attribute to the two nonequivalent nitrogen atoms in a vertically adsorbed Nj molecule and draw the analogy with the splittings observed in dinitrogen complexes of transition metals. The question that is immediately raised is the interpretation of the relatively high intensity of the satellite peak, some 60% of the main peak. Fuggle et al. (56) have considered this point. 

One conceivable way of fixing nitrogen is to split the N=N triple bond of dinitrogen bridging two metal atoms as shown in Eq. (10). 

This photogeneration of ammonia in the gas phase was interpreted by the authors (Endoh et al. 1986) as follow firstly, H20 molecules adsorbed on W03 x are split into hydrogen and oxygen under U V-irradiation, followed by reaction of the dinitrogen with hydrogen to produce ammonia. 

In the successive protonation reactions (Reaction sequence 11), the degradation of the strong triple bond of dinitrogen is achieved neither by splitting nor saturating it directly. Rather, as protonation of... 

The experiments of Falecki, Mint, Slebodzinski and T. Urbanski [185a] mentioned below also suggest that under the action of y- radiation dinitrogen tetroxide is split mainly into ions N02+ or (even more likely) into free radicals. N02 (according to eqn. 19). 

An electric discharge in a N2 atmosphere in the pressure range l.O-O.lhPa splits dinitrogen molecules to atomic nitrogen. This is accompanied by a peach-yellow glow that persists for up to 6 h after stopping the discharge. ... 

Apart from water splitting, T102 used in the form of particles or as a photoelectrode has been shown to catalyse also numerous other photoreactions. They include so different processes as, for example, photodegradation of chlorinated hydrocarbons " " hydroxylation of aromatic hydrocarbons photoreduction of dinitrogen water-gas shift reaction ... 

It thus requires more energy to split the dinitrogen molecule into two nitrogen atoms than to obtain two oxygen atoms from 02. This is what we would expect from the bond orders. Similarly, the bond length of N2 (110 pm) is less than that of 02 (121 pm). 

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