Scalar Relaxation of the Second Kind. A Potential Source of Information on the Dynamics of Molecular Movements. 3. A 13C Nuclear Spin Relaxation Study of CBrX3 (X = Cl, CH3, Br) Molecules

• DOI: 10.1021/jp501064c
• Publication Date: 2014-03-31T14:21:11Z
• Authors: Dominika Kubica; Artur Wodyński; Anna Kraska-Dziad...; Adam Gryff-Keller
• Keywords: Coupling constant; Isotopomers

Continuing studies based on measurements of the nuclear spin relaxation rates running via SC2 mechanism (scalar second kind), we present in this work results obtained for three bromo compounds: CBrCl3, (CH3)3CBr, and CBr4. A careful separation saturation-recovery curves, measured signals (13)C nuclei at 7.05 11.7 T two components, has provided longitudinal carbon (79)Br (81)Br containing isotopomers investigated compounds. These data have enabled experimental determination spin-spin coupling constants quadrupole bromine nuclei, both types parameters being hardly accessible by direct measurements. Investigation behavior these molecules, similar size shape, quite different practical interpretational problems which are likely to be encountered many other carbon-bromine systems. In order evaluate quality results, advanced theoretical calculations indirect (1)J((13)C,(79)Br) constants, magnetic shielding bromines compounds been performed compared with values. Relatively small divergences between experiment theory found. The contributions relativistic effects values discussed tentatively estimated.