A triple resonance hyperfine sublevel correlation experiment for assignment of electron-nuclear double resonance lines.
A new, triple resonance, pulse electron paramagnetic resonance (EPR) sequence is described. It provides spin links between forbidden electron spin transitions (DeltaM(S)=+/-1, DeltaM(I) not equal 0) and allowed nuclear spin transitions (DeltaM(I) = +/-1), thus, facilitating the assignment of nuclear frequencies to their respective electron spin manifolds and paramagnetic centers. It also yields the relative signs of the hyperfine couplings of the different nuclei. The technique is based on the combination of electron-nuclear double resonance (ENDOR) and electron-electron double resonance (ELDOR)-detected NMR experiments in a way similar to the TRIPLE experiment. The feasibility and the information content of the method are demonstrated first on a single crystal of Cu-doped L-histidine and then on a frozen solution of a Cu-histidine complex.
Potapov
Alexey
A
Chemical Physics Department, Weizmann Institute of Science, Rehovot 76100, Israel.
Epel
Boris
B
Goldfarb
Daniella
D
D003300:Copper / Q000737:chemistry*; D004578:Electron Spin Resonance Spectroscopy / Q000379:methods; D006639:Histidine / Q000737:chemistry*
D006639:Histidine; D003300:Copper