Nuclear quadrupole resonance theory

Nuclear Quadrupole Resonance, Theory Janez Seliger Pages 1672-1680... 

The third problem also concerns the choice of whether to leave out certain material. In a book of this size it is not possible to cover all branches of spectroscopy. Such decisions are difficult ones but I have chosen not to include spin resonance spectroscopy (NMR and ESR), nuclear quadrupole resonance spectroscopy (NQR), and Mossbauer spectroscopy. The exclusion of these areas, which have been well covered in other texts, has been caused, I suppose, by the inclusion, in Chapter 8, of photoelectron spectroscopy (ultraviolet and X-ray), Auger electron spectroscopy, and extended X-ray absorption fine structure, including applications to studies of solid surfaces, and, in Chapter 9, the theory and some examples of lasers and some of their uses in spectroscopy. Most of the material in these two chapters will not be found in comparable texts but is of very great importance in spectroscopy today. 

Nuclear quadrupole resonance spectroscopy (NQR) is a very direct and experimentally quite simple method for studying the interaction between the electric quadrupole moment of a nucleus and the electric field gradient at its site. Since the discovery of the method by Dehmelt and Kruger 3>6) in 1950, a large amount of experimental material has been collected, most of which has been interpreted within the frame of semiempirical theories. 

T. P. Das and E. L. Flahn, Nuclear Quadrupole Resonance Spectroscopy (Supplement 1 in the series Solid State Physics) Academic Press, New York, 1958, The classic early work on NQR theory. 

G. K. Semin, T. A. Babushkina and G. G. Yakobson, Nuclear Quadrupole Resonance in Chemistry , John Whey Sons, New York, 1975, A good catalog ofNQR frequencies, e Qq values, and T) values as well as a summary ofNQR theory and applications. 

The central idea of van Vleck has also been appUed to the field of nuclear quadrupole resonances, still in the solid state. We would also like to mention the well-known work of Gordon,who studied molecular spectra in terms of moments. His investigation provides examples of application of the moment theory in the gas phase. ... 

The existence of an electric quadrupole interaction is one of the most useful features of Mossbauer spectroscopy. The theory is closely related to that used in nuclear quadrupole resonance spectroscopy [14, 15). Any nucleus with a spin quantum number of greater than / = 4 has a non-spherical charge distribution, which if expanded as a series of multipoles contains a quadrupole term. The magnitude of the charge deformation is described as the nuclear quadrupole moment Q, given by... 

CW = continuous-wave CW-NQR = continuous wave NQR DFT = density functional theory EFG = electric field gradient IR = infrared NMR = nuclear magnetic resonance NQR = nuclear quadrupole resonance OSSE = octahedral site stabilization energy PAC = perturbed angular correlation pulse-FT = pulse-fourier transform TMED = tetramethylethylenediamine. 

See also Mossbauer Spectrometers Mossbauer Spectroscopy, Applications Mossbauer Spectroscopy, Theory NQR, Theory Nuclear Quadrupole Resonance, Instrumentation. 

See also Fourier Transformation and Sampling Theory NMR in Anisotropic Systems, Theory NMR of Solids NMR Pulse Sequences NMR Spectrometers Nuclear Quadrupole Resonance, Applications Soiid State NMR, Methods. 

See also ATR and Reflectance IR Spectroscopy, Applications IR Spectral Group Frequencies of Organic Compounds Nuclear Quadrupole Resonance, Instrumentation Photoacoustic Spectroscopy, Applications Rayleigh Scattering and Raman Spectroscopy, Theory. 

The quadrupole perturbed NMR spectriun of Rb (I = 312) consists of the central hne and two satelUte Unes. In D-RADP-x the nuclear quadrupole couphng constant decreases linearly with x from 9.6 MHz (x = 0) to 6.6 MHz (x = 0.95) [10], whereas the Larmor frequency amounts to 98.163 MHz in a Bo field of 7 T. Due to the substitutional disorder, and the corresponding loss of the translational invariance, the satelHte transitions are inhomogeneously broadened that much, that only the central transition can be directly observed. The position of the corresponding resonance line can be calculated using standard NMR-NQR theory [16], where the second order shift is given by ... 

A BRIEF REVIEW of the research in semiconductor surface physics is presented. Emphasis is placed on die limits of present theory and the importance of knowing the composition and structure of the surface of interest. The feasibility of new experimental approaches to the study of surfaces such as nuclear magnetic resonance and quadrupole res -onance is discussed. A review of recent developments in an understanding of the energy level diagram of the cleaned germanium surface is reviewed. 

Man, P. P. Quadrupole Couplings in Nuclear Magnetic Resonance, General. In Encyclopedia of Analytical Chemistry Applications, Theory and... 

S04 ions were compared with the results of quantum-chemical calculations. Manninen et al. presented an analytic response theory formulation for the leading-order magnetic field-induced and field-dependent quadrupole splitting in nuclear magnetic resonance spectra by first-principles calculations for Ne, Ar, and Kr in noble gas atoms. The case of molecules was studied for in the sulphur hexafluoride molecule. 

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