Structural phase transitions initiating the Peierls transition in di-perylene hexafluorophosphate

High-resolution conduction-electron spin g-factor analysis is used in order to monitor the molecular reorientations in the high-temperature metal phase of a perylene radical cation salt with 5/8-filled conduction band and Peierls transition at T-p=118 K. Well defined transition temperatures, but sample dependent reorientations are derived.