Oxygen, magnetic moment

The " N nucleus (/ = 1, 99%) has a moderately large magnetic moment and hyperfine splittings from this nucleus are a distinctive feature of the EPR spectra of chalcogen-nitrogen radicals. A-Arylthio-2,4,6-triphenylanilino radicals (3.16) are exceptionally persistent and oxygen-insensitive m solution. They exhibit a characteristic 1 1 1... 

Hund37 in 1926 and of oxygen and nitric oxide by Van Vleck38 in 1928 were triumphs of the theory of spectra. The magnetic moment of an atom or monatomic ion with Russell-Saunders coupling of the quantum vectors is... 

Hyperfine interaction has also been used to study adsorption sites on several catalysts. One paramagnetic probe is the same superoxide ion formed from oxygen-16, which has no nuclear magnetic moment. Examination of the spectrum shown in Fig. 5 shows that the adsorbed molecule ion reacts rather strongly with one aluminum atom in a decationated zeolite (S3). The spectrum can be resolved into three sets of six hyperfine lines. Each set of lines represents the hyperfine interaction with WA1 (I = f) along one of the three principal axes. The fairly uniform splitting in the three directions indicates that the impaired electron is mixing with an... 

Solutions of CrCl2-2CH3CN and the wet solid are extremely sensitive to oxygen. When dried, however, the complex remains unchanged in air for several minutes before oxidation becomes apparent. It is virtually insoluble in acetonitrile but quite soluble in ethanol. The room-temperature magnetic moment (4.8 B.M.) and electronic spectrum are consistent with a high-spin distorted octahedral Cr2+ ion.15... 

To treat the orientational structure of the monolayer formed by 02 molecules on a graphite surface, allowance must be made for the fact that an oxygen molecule is characterized not only by a nonzero magnetic moment but also by a record small quadrupole moment, so that dispersion interactions prevail over quadrupole interactions at intermolecular distances shorter than 10 A.79 In addition, the adsorbate lattice parameters give rise to very small minimum intermolecular distances, a 3.3 A, the parameter b 8.1 A markedly exceeding the values a. That is why, it is sufficient to consider only the nearest-neighbor interactions in a... 

Consider the available fluorine sites to be the lattice positions of a cubic, close-packed, two-dimensional lattice. These are the oxygen positions of a cubic, close-packed, oxygen lattice in the (111) type planes. Aluminum ions are situated below this two-dimensional anion layer. Suppose a fraction f of all the sites is randomly occupied by fluorine atoms the remaining sites are occupied by O with zero magnetic moment. 

HC 0 plane, the rotational strength as a function of HCOH dihedral angle can be detemiined for the chatge flow model. Similar calculations using the localized MO model showed that recoil of the C causes the oxygen lone pairs to rotate, generating the magnetic moment for this model. 

Nuclides with spin 7=0 therefore have no nuclear magnetic moment. Two very important nuclei, the isotope of carbon and the isotope of oxygen, belong to this class of nuclides—this means that the main building blocks of organic compounds cannot be observed by NMR spectroscopy. 

Magnetic coupling, between dimeric iron ions, diiron-oxygen proteins, 43 365-366 Magnetic interactions, 20 134-142 direct cation-cation, 20 139, 140 indirect cation-anion-cation, 20 140-142 Magnetic measurements, 32 58 Magnetic moments... 

Ferrite compounds with the inverse spinel structure are similar to magnetite, with different ions substituting for the iron atoms. As with FeO (cf. Figure 6.62), the oxygen ions have no permanent magnetic moment. Tetrahedral sites in the FCC oxygen array are occupied by half of the trivalent cations, and octahedral sites are occupied equally by divalent cations and the remaining trivalent cations. 

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