Abstract
Electron spin resonance techniques have been used to investigate the kinetics of the establishment of equilibrium of population distribution between nearest and next nearest neighbour Mn2+- vacancy dipoles. It is shown that the process involves W3, the rate at which a next nearest-neighbour vacancy exchanges with a particular nearest neighbour Na+, and W4, the rate of the inverse process to that of W3. In the range of temperatures investigated (-120 to +220 degrees C) these jump frequencies may be expressed in the Arrhenius forms W3=A2 exp(-E2/kT) and W4=A1 exp (-E1/kT) with the values: A1=1.059*1014+or-0.01*1014s-1, E1=0.67107+or-0.001 eV; A2=7.357*1013+or-0.01*1013 s-1, E2=0.63185+or-0.001 eV.