Publications by authors named "Ronald Derocher"
We describe the design and implementation of the instrumentation required to perform DNP-NMR at higher field strengths than previously demonstrated, and report the first magic-angle spinning (MAS) DNP-NMR experiments performed at (1)H/e(-) frequencies of 700 MHz/460 GHz. The extension of DNP-NMR to 16.4 T has required the development of probe technology, cryogenics, gyrotrons, and microwave transmission lines.
View Article and Find Full Text PDFWe described a versatile spectrometer designed for the study of dynamic nuclear polarization (DNP) at low temperatures and high fields. The instrument functions both as an NMR spectrometer operating at 212 MHz ((1)H frequency) with DNP capabilities, and as a pulsed-EPR operating at 140 GHz. A coiled TE(011) resonator acts as both an NMR coil and microwave resonator, and a double balanced ((1)H, (13)C) radio frequency circuit greatly stabilizes the NMR performance.
View Article and Find Full Text PDFArticle Synopsis
- The cryogenic sample exchange system enhances the efficiency of magic angle spinning (MAS) dynamic nuclear polarization (DNP) experiments by significantly reducing sample change time and improving instrument stability.
- The traditional process of changing samples in MAS DNP/NMR experiments is time-consuming, requiring hours to complete various steps, including warming the probe and reconnecting all necessary components.
- The new system employs an eject pipe and vacuum jacketed dewar to streamline this process, enabling faster, high-precision measurements on complex samples like bacteriorhodopsin and demonstrating excellent sensitivity with narrow linewidths in spectroscopy.