Indirect detection of selective nuclear spin-spin interactions in a hostile environment

We present a number of techniques which may be used to obtain precise values of selective spin-spin interactions between two nuclear spins in a hostile environment. Such an environment may be characterized by very fast relaxation and decoherence, e.g. due to the strong coupling of the two spins of interest to electron spins in their vicinity as well as other nuclei. Here, we used dilute paramagnetic Ce3+ centers hosted in a single crystal of CaF2. Selected 19F internuclear interactions were measured indirectly by applying different electron nuclear double resonance (ENDOR) pulse sequences.