1H NMR and DFT study of proton exchange in heterogeneous structures of pyridine-N-oxide/HCl/DCl/H2O |
| |
Authors: | Balevicius Vytautas Aidas Kestutis Tamuliene Jelena Fuess Hartmut |
| |
Affiliation: | Faculty of Physics, Vilnius University, Sauletekio 9, LT-10222 Vilnius, Lithuania. vytautas.balevicius@ff.vu.lt |
| |
Abstract: | Moderately narrow 1H NMR signals were observed in the solid-phase obtained from pyridine-N-oxide (PyO)...HCl solutions in acetonitrile/H2O after heterogeneous phase separation. High-resolution 1H NMR spectra are compared with those of crystalline PyO...HCl and PyO...DCl. It is concluded that partially resolved peaks in 1H NMR spectra of solids are related with heterogeneity of the spin system and the presence of different mobile H-bond clusters containing PyO, HCl, DCl and water molecules. Some part of non-bonded water or HCl molecules is captured in the cavities of crystalline samples. The attribution of the 1H NMR signals was based on the density functional theory calculation of proton magnetic screening tensor of the most expected H-bond structures in the 6-311G** basis taking into account the solvent effect by the polarized continuum model. |
| |
Keywords: | |
本文献已被 PubMed 等数据库收录! |
|