High-spin organic molecules with dominant spin-orbit contribution to magnetic anisotropy
are reported. Quintet 4-azido-3, 5-dibromopyridyl-2, 6-dinitrene (Q-1), quintet 2-azido-3, 5-
dibromopyridyl-4, 6-dinitrene (Q-2), and septet 3, 5-dibromopyridyl-2, 4, 6-trinitrene (S-1)
were generated in solid argon matrices by ultraviolet irradiation of 2, 4, 6-triazido-3, 5-
dibromopyridine. The zero-field splitting (ZFS) parameters, derived from electron spin
resonance spectra, show unprecedentedly large magnitudes of the parameters D:| D Q1 …