Beschreibung:
<jats:title>Abstract</jats:title><jats:p>Nuclear magnetic resonance (NMR) is an established method to determine self‐diffusion coefficients in liquids with high precision. The development of benchtop NMR spectrometers makes the method accessible to a wider community. In most cases, <jats:sup>1</jats:sup>H NMR spectroscopy is used to determine self‐diffusion coefficients due to its high sensitivity. However, especially when using benchtop NMR spectrometers for the investigation of complex mixtures, the signals in <jats:sup>1</jats:sup>H NMR spectra can overlap, hindering the precise determination of self‐diffusion coefficients. In <jats:sup>13</jats:sup>C NMR spectroscopy, the signals of different compounds are generally well resolved. However, the sensitivity of <jats:sup>13</jats:sup>C NMR is significantly lower than that of <jats:sup>1</jats:sup>H NMR spectroscopy leading to very long measurement times, which makes diffusion coefficient measurements based on <jats:sup>13</jats:sup>C NMR practically infeasible with benchtop NMR spectrometers. To circumvent this problem, we have combined two known pulse sequences, one for polarization transfer from <jats:sup>1</jats:sup>H to the <jats:sup>13</jats:sup>C nuclei (PENDANT) and one for the measurement of diffusion coefficients (PFG). The new method (PENPFG) was used to measure the self‐diffusion coefficients of three pure solvents (acetonitrile, ethanol and 1‐propanol) as well as in all their binary mixtures and the ternary mixture at various compositions. For comparison, also measurements of the same systems were carried out with a standard PFG‐NMR routine on a high‐field NMR instrument. The results are in good agreement and show that PENPFG is a useful tool for the measurement of the absolute value of the self‐diffusion coefficients in complex liquid mixtures with benchtop NMR spectrometers.</jats:p>