FERROELASTIC PHASE-TRANSITION OF PB-3(PO4)(2) SINGLE-CRYSTAL STUDIED BY ELECTRON-PARAMAGNETIC-RESONANCE

Lead phosphate is a typical ferroelastic material. We adopted the EPR of Cr3+ as a probe to investigate the phase transition and obtained th e phase transition temperature as 456.0 +/- 0.5 K. The variation of re sonance fields and intensities of Cr3+ signals versus temperature were investigated. Two sets of EPR signals in the bc-plane were measured w ith X-band, originated from the domains separated by the W-m-walls (mi rror planes) at the low temperature phase. Just above T-c, the coexist ence of the ferro- and paraelastic phase was observed and discussed.