Stadler Eduard, Dommaschk Marcel, Frühwirt Philipp, Herges Rainer, Gescheidt Georg
Institut für Physikalische und Theoretische Chemie, Technische Universität Graz, Stremayrgasse 9, 8010 Graz, Austria.
Institut für Organische Chemie, Otto-Hahn-Platz 4, 24098, Kiel, Germany.
Chemphyschem. 2018 Mar 5;19(5):571-574. doi: 10.1002/cphc.201701304. Epub 2018 Jan 25.
Increasing the signal-to-noise ratio is one of the major goals in the field of NMR spectroscopy. In this proof of concept, we accelerate relaxation during an NMR pulse sequence using photo-generated paramagnetic states of an inert sensitizer. For the follow-up acquisition period, the system is converted to a diamagnetic state. The reversibility of the photo-induced switching allows extensive repetition required for multidimensional NMR. We thus eliminate the obstacle of line-broadening by the presence of paramagnetic species. In this contribution, we show how cycling of synchronized light/pulse sequences leads to an enhanced efficiency in multidimensional NMR. Our approach utilizes a molecular spin switch reversibly altering between a paramagnetic and diamagnetic state.
