Spectra metal azides

The most extensive investigations of the infra-red and Raman spectra of metal azides were made by Gray and Waddington [34]. The Raman spectrum of azides was studied by Kahovec et al. [35], Kohlrausch and Wagner [36], and Sheinker and Syrkin [21]. 

Other Azides. Preliminary absorption spectra of CUN3 [86], CdNe, and HgNg [121] have been reported by Deb. Thin films were prepared by the solid-solid reaction technique described for PbNg. Mixed crystal systems of metal azide halides were probably formed in the reactions, since the results differed for each combination of alkali azide-metal halide. An earlier CUN3 spectrum was interpreted by Evans and Yoffe [82] to indicate an w = 1 exciton, but here again that appears theoretically unsound (Section C.3.b). 

An apparently similar catalase has also been isolated from the bacterium T. thermophilus (163). The enzyme is approximately 210 kDa each subunit is 34 kDa, indicating the existence of six subunits. The visible spectrum of the enzyme has a maximum near 440 nm (e = 7.7 x 102 M 1 cm-1) with shoulders at 460 and 500 nm. The similarity of the visible spectrum when compared to that of the pseudocatalase of L. plantarum led the authors to speculate that this might be a Mn pseudocatalase however, no metal analyses were reported. Additionally, the enzyme was inhibited by hydroxylamine, but it was also sensitive to azide. 

X-Ray photoelectron spectroscopy of the N(ls) core-electron binding energies of azides containing the alkali metals indicates that the electronic structure of the Nj ion is largely unchanged from compound to compound, and the differing thermal stabilities cannot be explained on the basis of different electronic structure. The N(ls) spectrum consists of two peaks in the vicinity of 398.5—404.9 eV separated by ca. 4.4 eV, as shown in the upper part of Table 6. The peak for terminal N is slightly broader than that... 

The absorption spectrum of [Ru "(HL)(H20)] at pH 5.3, which is identical to that at pH 2.8, changed upon the addition of sodium azide. The colour of the solution rapidly turned from pale yellow to reddish brown producing a new absorption peak at 450 nm (Figure 1C) with an isobestic point at 380 nm. These spectral changes were accounted for the rapid coordination of hydrazine, phenylhydrazine and azide ions into the metal center. The plots of change in absorbance (AA) vs [X]/ [Ru (HL)(H20)] (where [X] = N2H5, N2H4Ph and N3" ion) have confirmed the reaction stoichiometry was 1 1. 

The optical spectrum of iron superoxide dismutase is characterized by a broad band near 350 nm that is attributoi to a li nd-to-metal charge transfer band. The relatively high energy for this transition indicates that tyrosine is not a ligand to the Fe(lII). The EPR-spectrum is characteristically rhombic Azide and fluoride are inhibitors of the enzymatic activity. Intriguinly, cyanide does not affect the catalytic action. As in the case with the Cu ZHj enzymes, hydro n peroxide readily destroys the reactivity of iron SOD s, whereas manganese superoxide dismutases remain unaffected... 

Azide ion, both free and bound to metal-ion complexes, also absorbs strongly in this range. A comparison between the infrared spectra of azide bound to diethylene-triamine Zn(II) and Co(II) complexes or to the cobalt-enzyme and the corresponding spectrum for the native enzyme showed that the azide ion is coordinate to the Zn(II) atom of the native enzyme. Examination of the difference spectra in the presence of both azide and CO2 showed that the bound azide sterically interferes with the binding of CO2 in the hydrophobic cavity adjacent to the Zn(ll). 

The mononuclear and oligonuclear thiocyanate and azide compounds K[PcCo(NCS)]2, [PcM(SCN)] (M = Mn, Fe, Co) and [PcM(N3)] (M=Cr, Mn) were characterized by IR- and FIR-spectroscopy, magnetic measurements, thermogravimetrical, microanalytical and powder diffraction analysis [117]. The IR spectrum of K[PcCo(NCS)2] shows an intense CN valence frequency at 2095 cm" In agreement with former investigations on metal-thiocyanate complexes the frequency shifts to higher energy in [PcCo(SCN)] [119] compared to the mononuclear K[PcCo(NCS)2] [131]. 

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