In orientationally disordered solids, the anisotropy of spin interactions can cause a spectral line-broadening that severely complicates the acquisition and analysis of ESEEM (electron spin echo envelope modulation) spectra. The reduction or removal of powderbroadening is accomplished in ESEEM spectroscopy through the cancellation of antagonistic, static interactions. Three, distinct examples of this approach to spectral line-narrowing in nuclear spin one-half systems are described, together with their implications regarding the determination of electron-nuclear dipolar couplings. Applications involving15N and1H nuclei in protein and model systems are discussed.
ASJC Scopus subject areas
- Atomic and Molecular Physics, and Optics