CPMAS HFX WB triple resonance probe 0.7 mm

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The University of Bayreuth plans the purchase of a CPMAS HFX triple resonance probe with a rotor diameter of 0.7 mm for the 600 MHz WB solid-state NMR spectrometer (Avance III HD, Bruker) of the North Bavarian NMR centre. The responsibility for the procurement and an efficient scientific use is located in the work group of Juergen Senker (Inorganic Chemistry III). Additionally, the research groups of Seema Agarwal (Macromolecular Chemistry II) and Roland Marschall (Physical Chemistry III) expressed their interest in using the probe for their scientific research.With the purchase of the 0.7 mm MAS probe, we aim at implementing high-resolution solid-state NMR spectroscopy mainly based on protons for characterising of inorganic, organic, hybrid and polymer materials. Doing so, requires a probe able to spin fast enough to even average very strong homonuclear 1H-1H dipolar couplings effectively. Recent results suggest that these conditions become to be fulfilled beyond spinning speeds of 100 kHz. As the 0.7 mm MAS probe allows for rotation frequencies up to 110 kHz, it meets the necessary requirements. Under these conditions 1H MAS NMR spectroscopy features excellent sensitivities and allows for probing homonuclear spatial proximities up to roughly 1 nm. 1H MAS NMR experiments approach liquid-like conditions for the time dependence of NMR observables and thus enables to work with indirect detections schemes in the solid state. Besides of being able to record high-resolution 1H MAS NMR spectra, free of influences of the homonuclear dipolar coupling, and to acquire 1H-1H ZQ and DQ recoupling experiments more easily, indirect detection provides a promising alternative, for a broad range of heteronuclear correlation experiments. A successful handling of the proposed research topics, requires high-resolution proton HETCOR spectra with X nuclei like 6/7Li, 13C, 14N, 17O, 19F, 23Na, 27Al, 29Si, 69Ga, 91Zr, 113Cd and 119Sn. Some of these heteronuclei like 14N and 17O are difficult to excite directly. For the planned correlation experiments between 1H and 19F, additionally, a triple resonance setup with the possibility of simultaneously excite 1H, 19F and one further X nucleus is required.