Triplet States in Polydiacetylenes: T-ADMR in Zero Field Between 1.2 and 230 K

Using T-ADMR in zero-field on PDA TS-6 we could follow the triplet signals up to room temperature. The doubling of the number of triplet states resolved below 60 K is interpreted by a further phase- transition at this temperature with a rearrangement of the sidegroups. On PDA FBS the doublet structure found at 1.2 K is lost already at 7 K.