Structural phase transitions in langbeinites: an EPR study

摘要: The mechanism of structural phase transitions in langbeinites has been examined by EPR, taking Mn2+:Rb2Cd2(SO4)3 and VO2+:(NH4)2Cd2(SO4)3 as case studies. These studies suggest that the softening SO42- rotational modes is primarily responsible for this family. vanadyl dopant, which forms rigid oxygen octahedral coordination, found to stabilise low-temperature phase, locally, at temperatures much higher than actual transition point. Furthermore, indications were obtained points, -144 -170 degrees C, are probably associated with onset completion, respectively, slowing down rotations timescale EPR.