Mp. Trubitsyn et al., AN EPR STUDY OF LOCAL FLUCTUATIONS IN THE VICINITY OF THE FERROELECTRIC PHASE-TRANSITION IN LI2GE7O15, Physics of the solid state, 40(1), 1998, pp. 98-100
EPR spectra of Mn2+ ions have been studied in the temperature interval
containing the ferroelectric transition in crystalline lithium heptag
ermanate Li2Ge7O15. The EPR linewidth and shape were measured as funct
ions of temperature and orientation. It is shown that the critical res
onance-line broadening observed to occur in the vicinity of the phase
transition is due to fluctuations in the local order parameter with fr
equencies below 10(7) Hz. (C) 1998 American Institute of Physics.