Comparison of the simulated and experimental EPR spectrum of DDH with anAdoCbl in the absence of (R,S)-1,2-propanediol. The ZFS parameters were D = −335 G and E = −87 G, with Euler angles ζ = 71°, η = −10°, and ξ = 90°. The g-values for cob(II)alamin and the anhydroadenosyl radical gx = 2.30, gy = 2.21, gz = 2.00 and giso = 2.00, respectively. The 59Co-hyperfine splittings were Ax = 15 G, Ay = 5 G and Az = 113 G. Lorentzian line shapes were used with isotropic line widths of 55 G. The inset compares the simulated and experimental EPR spectrum of the half-field transition, obtained with the same parameter set.