ELDOR-detected NMR Spectroscopy at 115/230 GHz

Electron-electron double resonance (ELDOR)-detected NMR (EDNMR) spectroscopy is one type of the EPR based hyperfine spectroscopy techniques, which is used to detect hyperfine couplings between magnetic nuclei and unpaired electrons, which are too small to be resolved in the conventional EPR spectrum. Compared with other commonly used hyperfine spectroscopy, for instance, ESEEM (electron spin echo envelop modulation) and ENDOR (electron nuclear double resonance), HF EDNMR has advantages of higher sensitivity and finer spectral resolution enabling high-resolution hyperfine spectroscopy at room temperature. In this presentation, we present the principle and implementation of EDNMR in our 115/230 GHz EPR spectrometer at USC, and demonstrate the strategies to obtain high quality EDNMR spectrum by the employment of EDNMR on a standard sample. In addition, we discuss applications of HF EDNMR on the study of solid-state spin systems.