Year: 1978
Type: article
Abstract: The19F-self-diffusion has been investigated in PbF2, up to the melting point, by NMR techniques. Relaxation time measurements (T1, T2and T1 rho) have been made from 300 to 1095K. Anomalous behaviour above 500K, similar to that reported in previous investigations, is found to be due to paramagnetic impurity produced as a result of the high reactivity of PbF2at these temperatures. Direct F-diffusion measurements have been made using NMR spin echoes from 570K to 1005K. These results are compared with those of ionic conductivity and are found to be 0.88+or-0.10 eV, assuming a vacancy mechanism of self-diffusion is operative. Above the phase transition at 705K the F-diffusion coefficient changes more slowly with temperature, being characterised by an activation energy of 0.20+or-0.02 eV, which is typical of a fast ion conductor.
Authors: R E Gordon, J H Strange
Institution: University of Kent
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: bronze
OpenAlex ID: W2159489447