Magnetic molecular bistability in the crystals of heterocyclic thiazyl radicals

A large first-order magnetic phase transition in an organic radical, 1,3,5- trilhia-2,4,6-triazapentalenyl is described, that occurs with a wide therma l hysteresis loop over the temperature range from 230 to 305 K. The high-te mperature phase is paramagnetic, while the low-temperature phase is diamagn etic. The results reported here on room-temperature magnetic molecular bist ability may have applications in thermal sensors, switching units and infor mation storage media, based on organic radical crystals.