Molecular Nitrogen, Azido and Related Groups

The diazenido ligand in Mn((HN2)(CO)2P2, where P = P(OPh)3, has VN2 bands at 1589 and 1618 cm (two bands were seen due to Fermi resonance with a phenyl mode). For (terpy)Mn (N3)3, VasN3 bands were observed at 2072, 2035 cm-i (IR), 2071, 2046 cm (Raman).i  

The IR spectra of the reaction products of iron atoms and N2 trapped in low-temperature matrices include bands associated with FeNNN, Fe(NN), Fe(NN)2 and (in a pure N2 matrix) Fe(NN)6/ The complexes [(por)Fe(N2Re(PMe2Ph)4Cl], where por = OEP or TTP, have VN2 of the bridging dinitrogen ligand at 1803,1820 cm respectively. 

In addition, vNO bands are seen in the range 1950-1960 cm, consistent with a linear Ru -NO+ unit.  

The molecules ClNiNN, ClCuNN and BrCuNN were identified in matrix-IR spectra of the reaction products of laser-ablated MX2 with N2/Ar mixtures. vNN bands were seen at 2246.3,2296.3 and 2297.8 cm respectively. The photolysis of MX2, where X = Cl or Br, in N2 matrices leads to the formation of pseudo-tetrahedral NiX2(r -N2)2, with vNN at 2280.9, 2260.3 cm (Cl) or 2281.4, 2261.4 cm (Br).  

The complexes (41), where R = H, Me or Cl, have vN = N near 1385 cm about 40 cm lower than for the free ligand. The analogues with chlorines replaced by catecholato ligands have vN = N near 1355 cm - due to increased back-bonding to the tt N = N orbital. Azido-ligand modes were assigned from the vibrational spectra of [Pt(N3)6], [Pt(N3)Cl5] and their N-isotopomers -Table 

The complexes [CpMo(NNRPh)2(PPh3)], where R = Me or Ph, have vNN of the organo-hydrazido ligands at 1589 cm h Similar values were seen in Tp Mo(NNPPh)2Cl, where Tp = hydridotris(3,5-dimethylpyrazolyl)borate, R = Me or Ph. In Cp WCl3(NNPh2) vNN of the hydrazido ligand is at 1585 

The species (41) has vNN at 2013 cm (compared to 2117 cm Mn the corresponding Fe(II) complex), showing strong Fe N2 back-donation. Fe(N2)(depe)2, where depe = Et2PCH2CH2PEt2, has vN = N at 1955 cm-h This very low value shows strong donation from the electron-rich Fe(0) centre. In [FeX(N2)(depe)2], however, the values are much higher, at 2088 cm (X = C1) or 2091 cm (Br).  

The value of vNN for N2 adsorbed on ruthenium-containing catalysts is very sensitive to the electronic state of the active surface. The IR spectrum of N2 adsorbed on ruthenium catalysts supported on dealuminated zeolite Y contains bands due to Ru (N2)(CO) (VN2 2218 cmvCO 2123 cm ) and Ru (N2)2 (vN2 2207,2173 

Scandium atoms and N2 form a range of species trapped in low-temperature matrices, e.g. Sc(NN) (vNN 1902 cm ) and Sc(N2)2Sc (1599.5 cm ). Similar results were obtained from experiments with Y or La atoms and U or Th atoms and N2. 

The species (H2GaN3)n has VasN3 at 2130 cm and at 1238 cm. Polymeric Cs[(PhCH2)3lnN3] has VasN3 at 2026 cm, consistent with a considerable ionic contribution to the In-N3 binding, and 5N3 bands were also seen, at 1306 and 679 cm respectively.  

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Molecular Nitrogen, Azido- and Related Groups. - DRIFT data for N2 adsorbed on sodium mordenites gave evidence for both end-on and perpendicular coordination of the N2 to Na+.164 Ultrafast polarisation IR spectra were reported for v3 (vas) for azide in NaN3, MgN3+ and CaN3+ ion-pairs in dmso solutions.165... 

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