Go toArchive
Browse byFacets
Bookbag ( 0 )
'Electric Field Gradient Tensor' in keywords
Results  3 Items
Sorted by   
Publication Year
1999 (2)
1998 (1)
1Author    N. Sinyavsky, M. Maćkowiak, N. VelikiteRequires cookie*
 Title    Influence of the rf Field Inhomogeneity on Nutation NQR Spectra of Spin 3/2 Nuclei in Powders  
 Abstract    The influence of the rf field inhomogeneity on the NQR nutation spectra of spin / = 3/2 nuclei in powder samples is investigated. To eliminate the rf field inhomogeneity effects, a method of reconstruction of the NQR nutation spectra, based on finding the deconvolution of the Fourier nutation spectrum with a function of the rf field distribution, is used. The method is successfully demonstrated for simulated and experimental NQR nutation spectra of 35 C1 in TiCl 4 . The lineshape analysis of reconstructed nutation spectra allowing the determination of the EFG asymmetry parameter is given. The real advantage of the proposed method is that the high-resolution nutation spectrum may be obtained for a sample filling up the entire coil. 
  Reference    Z. Naturforsch. 54a, 153—158 (1999); received November 24 1998 
  Published    1999 
  Keywords    Nuclear Quadrupole Resonance, 2D Nutation Spectroscopy, Electric Field Gradient Tensor 
  Similar Items    Find
 TEI-XML for    default:Reihe_A/54/ZNA-1999-54a-0153.pdf 
 Identifier    ZNA-1999-54a-0153 
 Volume    54 
2Author    N. Velikite, N. Sinyavsky, M. MaćkowiakRequires cookie*
 Title    Lineshape Analysis of 2D NMR and NQR Nutation Spectra of Integer and Half-Integer Quadrupolar Nuclei  
 Abstract    A lineshape analysis of the NMR and NQR powder nutation spectra of integer and half-integer quadrupolar nuclei is presented. Simulated NMR nutation spectra of spin I = 1 and 3 nuclei are reported. For / = 1 the formulas for the singularities of the NMR nutation powder patterns as a functions of rj, e 2 Qq and 7B x are given. The NQR nutation powder patterns for spin / = 3/2, 5/2, 7/2, and 9/2 for different induced transitions are calculated, and some experimental aspects of the method are discussed. A universal empirical formula to facilitate the determination of the asymmetry parameter from the NQR nutation frequency singularities for any arbitrary spin or transition is found. The NQR nutation spectra for half-integer and integer spins are compared. For integer spins the two-frequency excitation of the nutation spectrum is analysed. Application of the 2D-nutation lineshape analysis for the determination of the quadrupole interaction parameters is emphasised. 
  Reference    Z. Naturforsch. 54a, 351—357 (1999); received April 9 1999 
  Published    1999 
  Keywords    2D Nutation Spectroscopy, NQR, NMR, Electric Field Gradient Tensor 
  Similar Items    Find
 TEI-XML for    default:Reihe_A/54/ZNA-1999-54a-0351.pdf 
 Identifier    ZNA-1999-54a-0351 
 Volume    54 
3Author    Mariusz Maćkowiak, Piotr KątowskiRequires cookie*
 Title    2D Off-Resonance Nutation NQR Spectroscopy of Spin 3/2 Nuclei  
 Abstract    The effects of off-resonance irradiation in nutation NQR experiments are demonstrated both experimentally and theoretically. The theoretical description of the off-resonance effects in 2D nutation NQR spectroscopy is given, and general exact formulas for the asymmetry parameter are obtained. It is shown that the outcome of the off-resonance nutation experiments depends on the data acquisition procedure, leading to one-or three-line nutation spectra. To explain this fact and to describe the off-resonance nutation experiment properly, the transient response theory of a quadrupolar spin system to an RF pulse was modified using the wave-function approach. The 2D separation of interactions technique has been applied to separate a static and a randomly time-fluctuating dynamic part of the quadrupole interaction in the antiferroelectric phase of poly-crystalline ammonium dihydrogen arsenate. Two-dimensional off-resonance nutation NQR spectroscopy has been used to determine the full quadrupolar tensor of spin-3/2 nuclei in several molecular crystals containing the 35 C1 and 75 As nuclei. The off-resonance phenomena in 2D NQR are very important from the practical point of view (determination of r\ in multiple or broad-line spectrum) and also provide interesting information on the dynamic properties of a quadrupolar spin system. 
  Reference    Z. Naturforsch. 53a, 285—292 (1998); received January 26 1998 
  Published    1998 
  Keywords    Nuclear Quadrupole Resonance, 2D Nutation Spectroscopy, Off-resonance Irradiation, Electric Field Gradient Tensor 
  Similar Items    Find
 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0285.pdf 
 Identifier    ZNA-1998-53a-0285 
 Volume    53