Quadrupole resonance

To find explosives Gas analyzers, chromatography instruments, drift-spectrometers, neutron defectosopes, nuclear-magnetic and nuclear-quadrupole resonant instruments... 

T. P. Das and E. L. Hahn, Nuclear Quadrupole Resonance Spectroscopy, Academic Press, New York, 1958, 223 pp E. A. C. Lucken, Nuclear Quadrupole Coupling Constants, Academic Press, London, 1969, 360 pp. 

The reduction of the C— Br and C—1 group moments from 1.10 and 0.90 in bromo- and iodo-benzene to about 0.80 and 0.50 in 2-bromo- and 2-iodo-thiophene has been ascribed to the larger weight of resonance forms such as (8) and (9) in the thiophene series. The chlorine, nuclear, quadrupole, resonance frequencies of chloro-substituted thiophenes are much higher than those of the corresponding benzene derivatives. This has been ascribed to a relayed inductive effect originating in the polarity of the C—S o-bond in thiophenes. The refractive indices, densities, and surface tension of thiophene, alkyl- and halo-thiophenes, and of some other derivatives have been... 

Greater reactivity gamma to an azine-nitrogen would be expected on the basis of the greater ara-quinoid than orf/io-quinoid interactions between various substituents and azine-nitrogens in ground states and excited states. Such a difference in interaction is supported by several kinds of data spectral,basicity, dipole moment, and chlorine quadrupole resonance of halo, methoxy,... 

QUADRUPOLE RESONANCE. This concept is based on the theory that the quadrupole resonance frequency of the chlorine nucleus in AP wiii vary with the particle size. This is because... 

Wachtell (Ref 23) worked on the application of this principle. However, early in his work a major problem was encountered in finding the quadrupole resonance of the chlorine nucleus which did not exist in the frequency range in which it had been expected (20—40 megacycles). Nuclear Magnetic Resonance studies finally have shown that this quadrupole resonance should exist around 150 kilocycles. Future studies of single crystals of AP should reveal the presence and the exact location of this resonance. If this can be done, then the analysis of particle size, based on the shift of the quadrupole resonance frequency, may be possible... 

Nuclear quadrupole resonance and its applications in inorganic chemistry. M. Kubo and D. Nakamura, Adv. Inorg. Chem. Radiochem., 1966, 8, 257-282 (78). 

Nuclear Quadrupole Resonance and Its Application in Inorganic Chemistry Masaji Kuho and Daiyu Nakamura... 

C1 Nuclear quadrupole resonance (n.q.r.) studies on PhPCli and PhjPCIa indicated non-equivalence of the chlorine atoms. However, a more recent report states that the spectra of these compounds and PCI5 all contain two signals corresponding to apical and radial chlorine atoms and that replacement of chlorine by phenyl occurs in the radial position. 

Several C1 nuclear quadrupole resonance (n.q.r.) studies have been carried out on chlorophosphorus compounds. - The frequencies observed for phenyldichlorophosphine are similar to those of phosphorus... 

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