Место издания:Saint-Peterburg, Solo puplishing Saint-Peterburg Russia
Первая страница:216
Последняя страница:216
Аннотация:NMR spectroscopy is a valuable method for studying of structure and properties of molecules in solution. Molecules with anisotropy of the magnetic susceptibility exhibit a small partial orientation in strong magnetic field. The resulting macroscopic anisotropy may become manifest anisotropic nuclear spin interactions, like the direct dipolar and quadruple coupling [1]. Methods based on this effect can provide information on the spatial structure of the compound. In the literature applications for DNA, peptides and their complexes are presented [2, 3].
Until recently, main source of information about orientation effects based on a quadrupole coupling in NMR 2H for selectively deuterated species. However, some experimental factors: extra efforts for synthesis of the compounds, fast quadrupole relaxation of deuterium signals and complicated procedure of the data processing, - limited the practical feasibility of this technique.
Augmentation of the basis set with polarization functions affects the values of the calculated parameters to a lesser extent compared to augmentation with diffuse functions. Calculated аanisotropy and rhombicity of the magnetic susceptibility tensor for the molecules under investigation and experimental ones are in good agreement.