Dinitrogen bond length

In the literature discussing these results, the coincidence of the NN bond lengths in diazonium ions with that in dinitrogen seems always to be regarded with complete satisfaction. In the opinion of the present author this close coincidence is somewhat surprising, firstly because of the fact that in diazonium ions one of the nitrogen atoms is bonded to another atom in addition to the N(2) atom, and secondly because work on dual substituent parameter evaluations of dediazoniation rates of substituted benzenediazonium ions clearly demonstrates that the nx orbitals of the N(l) nitrogen atom overlap with the aromatic 7t-electron system (see Sec. 8.4). 

Because the N2 molecule in the complex is still expected to have partial multiple bond character, the d-type functions could be needed. Therefore, d-type function have been added to nitrogen atoms (using a Gaussian exponent of 0.8) of the dinitrogen molecule. Our preliminary test of the effect of phosphorus atom d-type functions on the calculated Zr-PH3 bond lengths of model complexes A1 and A7 showed that the influence of d-type functions on the P atom is insignificant. Therefore, here we will not include d-type of functions for P-atoms. 

The coordination of the dinitrogen ligand is maintained when traTO-[Re(N2)Cl(dppe)2] is exposed to NaX salts (X = NCS, NCO , Ns ) in THF/MeOH solutions. The isothiocyanato and azido complexes of type (276) have been studied by X-ray structural analysis.A Re— N2 bond length of 1.951 A is observed for the NCS compound which is somewhat shorter than that in the starting material and indicates a considerable degree of double bond character. 

Dinitrogen Tetroxide.—The dimer of nitrogen dioxide is not very stable its enthalpy of formation from the monomer is 13.873 kcal/mole. The molecule is found in both the crystal (x-ray diffraction)29 and the gas (electron diffraction)80 to be planar, with orthorhombic symmetry. The N—N bond length reported for the crystal is 1.64 A. The value for the gas molecule, 1.75 A, is probably somewhat more accurate.81 This value is 0.28 A greater than the single-bond value found for hydrazine the bond number of the bond is accordingly about 0.34 (Equation 7-7). 

The very labile dinitrogen complex [Mo(CO)(N2)(Ph2PCH2-CH2PPh2)2] has been described in detail. Its immediate precursor, [Mo(CO)(Ph2PCH2CH2PPh2)2], is obtained by the reaction of [Mo(N2)2-(Ph2PCH2CH2PPh2)2] with, for example, benzyl propionate under carefully controlled conditions (283, 322). This precursor is square pyramidal in the solid state, with carbon monoxide at the apex and an essentially vacant coordination position trans to it. The CO bond length is 1.192(12) A, and v(CO) = 1690 cm 1, and the nearest ap-... 

Figure 15.1.5(f) shows a planar, side-on bonded N2 ligand between two Zr atoms in the compound [Cp"2Zr]2(N2) [Cp" = l,3-(SiMe2)2C5H3], The N-N bond length is 147 pm. Side-on coordination of the dinitrogen ligand appears to be important for its reduction. 

Dinitrogen pentoxide is a white solid that sublimes at 32 °C. The solid is ionic, N02+N03, with N02+ being linear (Dmh) as a result of it being a 16-electron triatomic species. The N-0 bond length in N02+ is 115 pm, and at low temperatures, the structure of N205 is... 

There has been a report of bridged dinitrogen complexes of iron(III) and chromium(lll) complexes, formed by reaction of the metallo(IlI)porphyrinate triftate with [Re(N2)(PMe2Ph)4Cl] to make the Fe-N-N-Re or Cr-N-N-Re bridged complexes. The Fe complex has a magnetic moment of about 4.4 /u-b at room temperature, consistent with a S = 312,512 admixed spin state for the iron(lll), and a pyrrole-H shift of -3.23 ppm, consistent with the expected weak-fteld nature of the N2 ligand. The stracture shows a linear Fe-N-N-Re unit (Fe-Nl-N2 = 170°, Nl-N2-Re = 177°) with Fe-N bond length of 1.93 similar to that of the TPPFe -azide complex (1.953 A). 

Dinitrogen tetroxide, N2O4, bp 21.2°C, no unpaired electrons, N—N bond length 1.64 A, N—O bond length 1.17A,... 

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