C-13, N-14 AND N-15 ENDOR MEASUREMENTS ON THE SINGLE SUBSTITUTIONAL NITROGEN CENTER (P1) IN DIAMOND

NeW ENDOR measurements on the single substitutional nitrogen centre in diamond are reported. The CW-ENDOR mechanism utilizes cross relaxation, and measurements have been made on both N-14 and N-15, as well as the first detailed C-13 ENDOR study on the isotope at the natural abundance of 1.1%. The change in EPR intensity induced by driving the C-13 nuclear transitions was approximately equal to 100% of the EPR intensity of the appropriate C-13 hyperfine satellite. The assignment of C-13 hyperfine coupling matrices with specific sites is considered, and predictions made about the signs of some of the C-13 hyperfine interactions.