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71.
72.
Thomas P.E.Auf Der Heyde Craig S. Green Derek E. Needham David A. Thornton Gareth M. Watkins 《Journal of Molecular Structure》1981
The infrared spectra of the complexes [M(pyO)(H2O)Cl2] (M = Mn, Fe, Co, Ni, Cu; pyO = pyridine N-oxide) have been determined. Assignments of ν M-Opy, νM-OH2 and ν M-Cl are made by observing the effects of deuterating the coordinated pyO and H2O and replacing chloride by bromide in the Mn(II) complex. Assignments of metal—ligand modes in the mixed ligand complexes [M(pyO)(dmso)X2] (dmso = dimethylsulphoxide) are made by comparison with the spectra of (ML2X2] (L = pyO, dmso) and by observing the effects of deuteration of pyO and dmso. Structural aspects of the spectra are discussed. 相似文献
73.
We present a detailed theoretical analysis for the determination of the total internal loss in Fabry-Perot resonators based on Fourier analysis of the emission or transmission spectrum. The observation of higher-order harmonics and their relative height in the Fourier-transformed spectrum allow us to quantify the total resonator loss. Because this new method considers both contrast and shape of the Fabry-Perot fringes it is especially well suited for the evaluation of high-finesse laser resonators such as those of vertical cavity surface-emitting lasers in terms of propagation loss/gain. 相似文献
74.
A. F. Joseph F. P. Treadwell W. T. Hall F. Sutton L. L. de Koninck J. M. Kolthoff F. W. Küster Fr. L. Hahn H. Windisch W. Böttger C. Russo A. Monnier O. Hackl W. M. Thornton jr. J. E. Chapman L. Brandt E. Knecht Eva Hibbert O. Tomiček E. Polidori B. Diethelm F. Foerster W. M. Thornton L. Moser W. A. Hicks K. Schröder 《Analytical and bioanalytical chemistry》1926,68(9-10):369-384
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The infrared spectra of eight complexes of general formula [ML2(NCS)2] (M = Co, Ni, Cu, Zn; L = aniline or p-toluidine) have been determined over the range 4000–4150 cm?1. Colour, magnetic moments and IR spectra are consistent with polymeric octahedral coordination in the Co(II) and Ni(II) complexes and polymeric tetragonal coordination in the Cu(II) complexes, while the Zn(II) complexes are assigned polymeric octahedral (L = aniline) and tetrahedral (L = p-toluidine) structure on the basis of their IR spectra. Independent 15N-labelling of the nitrogen atoms of the amino and isothiocyanate groups yields assignments for the internal vibrations of both groups and enables the metal-amine and metal—isothiocyanate stretching vibrations (vM-NH2 and vM-NCS) to be distinguished. Both vM-NH2 and vM-NCS are metal ion dependent in the Irving-Williams sequence (Co < Ni < Cu > Zn) expected from their proposed structures while the vN-H and vN-CS vibrations are inversely related to the masses of the coordinated metal ions. 相似文献
79.
The infrared spectra of the sodium salts and the Mn(II), Co(II), Ni(II), Cu(II) and Zn(Il) chelates of anthranilic acid and 5-methyl-, 5-chloro-, 5-bromo-and 5-iodo-anthranilic acid are discussed. 15N-Labelling of sodium anthranilate and the complexes of anthranilic acid provides assignments of the ligand vibrations involving the amino group. The metal-ligand stretching frequencies (vM-N and vM-O) are assigned by observing the effects on the spectra caused by 15N-labelling, metal ion substitution and ligand substitution. The vCu-O bands are split by tetragonal distortion in the Cu(II) complex which involves elongation of the axial Cu~O bonds. The metal ion dependence of vM-N and vM-O parallels the Irving-Williams stability sequence. The ligand substituents shift vM-O in accordance with their inductive effects while vM-N exhibits a substituent dependence which is roughly the opposite of that shown by vM-O. 相似文献
80.
Abstract The vibrational and electronic spectra of eleven complexes of copper(II) succinimide [CuSu2Am2] (Su = succinimide ion; Am = variously substituted primary aliphatic amines) show that metal-imide co-ordination occurs through the imide nitrogen atom. The electronic effects of the amine substituents on the carbonyl stretching frequencies and on the electronic spectra are used to infer the probable mechanism of metal-imide bonding. 相似文献