A general strategy for obtaining F-19-F-19 and C-13-F-19 residual dipolar couplings in perfluorocarbons from the NMR spectroscopy of liquid crystalline samples

作者：De Luca Giuseppina; Emsley James W^*; Salager Elodie; Lesage Anne

来源：Physical Chemistry Chemical Physics, 2010, 12(28): 7968-7976.

DOI：10.1039/c002817g

A two-dimensional Fluorine Detected Local Field (FDLF) NMR experiment is demonstrated on a sample of perfluoropropyl iodide dissolved in the nematic solvent ZLI1132. In analogy to the proton detected local field (PDLF) technique, for each resolved site of the carbon spectrum, a simple map of the heteronuclear coupling network is obtained in the indirect dimension. A full analysis of the FDLF spectrum was achieved with the aid of two-dimensional F-19-C-13 HETCOR and C-13, D-resolved spectra (with D representing the anisotropic spin-spin coupling). A one-dimensional F-19 spectrum was recorded on the same sample at intermediate resolution, and values of the residual spin-spin couplings T-CF and T-FF obtained from both experiments were combined and used to provide starting parameters for the analysis of a very high resolution F-19 spectrum, including the weak satellite lines from single-C-13 isotopomers. The high-precision, residual, anisotropic couplings were used to explore whether they have an appreciable contribution from the anisotropic electron-mediated spin-spin couplings.

• 出版日期2010