We have measured coercive field, remanent polarization, built-in bias field, and the dielectric constant and loss in Mn-doped lead scandium tantalatePbSc1/2Ta1/2O3thin films from 15–400 K. Evidence for four low-temperature anomalies near 50 K, 100 K, 160 K, and 233 K is summarized, and a discussion is presented of whether these are phase transitions. For comparison, ceramic samples were studied via X-ray techniques down to 20 K, and via DSC (differential scanning calorimetry) techniques near 233 K. ©2001 American Institute of Physics.