Metal atoms dinitrogen

A number of new metal-dinitrogen complexes of type M(N2) have been detected in the reaction of metal atoms with N2 under matrix isolation conditions. Most strikingly, nickel atoms and nitrogen give Ni(N2)4 (45). However, this is strictly a matrix species, and it decomposes on removal of the matrix gases even at very low temperatures. It appears to be stable up to -150°C isolated in an SF6 matrix. Mixed CO/N2 complexes have also been prepared in matrices but their stabilities outside the matrix are not reported (72). 

A special technique which has yielded highly unstable and simple dinitrogen complexes trapped in low-temperature solids (N2 or Ar) is the metal atom cocondensation technique in low-temperature matrices. By the cocondensation of nickel atoms and N2 at 4.2-10 K the binary compounds Ni(N2) (n = 1-4) result, whose structure has been inferred from IR and... 

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). 

Although N2 is isoelectronic with CO and RNC, and isosteric with the former, it is far more inert and the first dinitrogen complex, [Ru(NH3)5(N2)]2+, was discovered only in 1965. Dinitrogen can be bound to metal atoms only in the presence of other ligands there are no homoleptic complexes analogous to those formed by CO or RNC. 

With the similar molybdenum complex the yield of ammonia reaches only ca 0.7 mol per metal atom, the remainder being evolved as free dinitrogen, with molybdenum being oxidized to molybdenum(III). Apparently, however, no such complexes have been observed as intermediates in dinitrogen reduction in protic media. 

It should be mentioned that consecutive two-electron reduction of dinitrogen is still usually considered likely in the literature, with diazene, N2H2, as an intermediate but stabilized by complexation with transition metals. At the same time there is no doubt that both 7r-bonds of N2 can be used simultaneously for four d-electrons (entering two degenerate 7ig -orbitals) from one, two, or several metal atoms forming a complex with dinitrogen, and separate cleavage of each 71-bond seems to be unnecessary, more so because it is thermodynamically unfavorable. Therefore, for-... 

In the Cr/N2 system binary dinitrogen complexes of chromium with from one to six co-ordinated Nj ligands per metal atom have been identified from their i.r. spectra in argon/diniirogen matrices at 10 K. The u.v. spectrum of is qualitatively similar... 

The side-on bonding mode of dinitrogen remains very rare and there appear to be no structures recorded in the April 1993 version of the CSD. The side-on bonding mode of N2 is similar to the bonding mode of ethene, v here the 7r-bond of N2 donates electrons to the metal atom, and back-donation is from metal d-type orbitals to empty N2 7r -orbitals . ... 

Start with a binary molecular compound. Note that a binary molecular compound is composed only of two nonmetal atoms—not metal atoms or ions. An example is dinitrogen monoxide (N2O), a gaseous anesthetic that is more commonly known as nitrous oxide or laughing gas. The naming of nitrous oxide is explained in the following rules. 

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