Isotope Effects on the 17O, 1H Coupling Constant and the 17O-{1H} Nuclear Overhauser Effect in Water

The NMR spectra of solutions of 30% 17O-enriched H2O and D2O in nitromethane display the resonances of the three isotopomers H2O, HDO, and D2O. All 17O, 1H and 17O, 2H coupling constants and the primary and secondary isotope effects on J(17O, 1H) have been determined. The primary effect is -1.0 ± 0.2 Hz and the secondary effect is -0.07 ± 0.04 Hz. Using integrated intensities in the 17O NMR spectra, the equilibrium constant for the reaction H2O + D2O ⇌ 2HDO is found to be 3.68 ± 0.2 at 343 K. From the relative integrated intensities of proton-coupled and -decoupled spectra the 17O-{1H} NOE is estimated for the first time, resulting in values of 0.908 and 0.945 for H2O and HDO, respectively. This means that dipole-dipole interactions contribute about 2.5% to the overall 17O relaxation rate in H2O dissolved in nitromethane. © 1999 Academic Press.

Авторы
Sergeyev N.M.1 , Sergeyeva N.D. 2 , Raynes W.T.3
Редакторы
-
Издательство
Academic Press Inc.
Номер выпуска
2
Язык
Английский
Страницы
311-315
Статус
Опубликовано
Подразделение
-
Номер
-
Том
137
Год
1999
Организации
  • 1 Department of Chemistry, Moscow State University, 119899 Moscow, Russian Federation
  • 2 Russ. Peoples' Friendship University, 117198 Moscow, Russian Federation
  • 3 Department of Chemistry, University of Sheffield, Sheffield S3 7HF, United Kingdom
Ключевые слова
Isotope effects on coupling constants; NOE 17O-{1H}
Дата создания
19.10.2018
Дата изменения
19.10.2018
Постоянная ссылка
https://repository.rudn.ru/ru/records/article/record/605/