Magnetic relaxation in two 1D Tb-nitronyl nitroxide complexes

Abstract Reaction of the nitronyl nitroxide radical NIT-CH 3 and NIT-C 3 H 5 with Tb(hfac) 3 affords two one-dimensional lanthanide–nitronyl nitroxide compounds: [Tb III (hfac) 3 (NIT-CH 3 )] n ( 1 ), and [Tb III (hfac) 3 (NIT-C 3 H 5 )] n ( 2 ) (NIT-CH 3  = 2,4,4,5,5-pentamethylimidazolyl-1-oxyl-3-oxide; NIT-C 3 H 5  = 2-cyclopropyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide). Single crystal X-ray crystallographic analysis reveals that these two compounds are one-dimensional chains built up by Tb(hfac) 3 units bridged by radicals through their NO groups. Magnetic studies show that both Tb complexes exhibit frequency-dependent out-of-phase signals.