The diffusion of 44Ti in 4N-purity rutile was studied by using thin-layer deposition and serial sectioning. The results (table 15) could be described by:
a-axis: D(cm2/s) = 2.0 x 10-3exp[-48.5(kcal/mol)/RT]
c-axis: D(cm2/s) = 4.6 x 10-2exp[-59.9(kcal/mol)/RT]
Cation self-diffusion in TiO2 was studied both theoretically and experimentally and it as found that the relative diffusion coefficients in the a- and c-directions could be used, together with their partial correlation functions, to identify the jumps taking place in the body-centered tetragonal cation sub-lattice. Three possible types of jump were considered: a-direction, c-direction and body diagonal. The information obtained showed that the diagonal jump could not be unique for this system but had to be accompanied by a significant fraction of c-direction jumps.
Cation Self Diffusion in Rutile. Lundy, T.S., Coghlan, W.A.: Journal de Physique - Colloques, 1973, C9[34], 299-302
Table 15
Diffusion of 44Ti in rutile
Temperature (C) | Axis | D (cm2/s) |
1197 | c | 5.9 x 10-11 |
1247 | c | 1.36 x 10-10 |
1293 | c | 1.64 x 10-10 |
1347 | c | 3.56 x 10-10 |
1350 | c | 4.06 x 10-10 |
1398 | c | 6.74 x 10-10 |
1455 | c | 9.53 x 10-10 |
1477 | c | 1.825 x 10-9 |
1510 | c | 2.36 x 10-9 |
1197 | a | 1.617 x 10-10 |
1247 | a | 2.74 x 10-10 |
1293 | a | 5.88 x 10-10 |
1347 | a | 4.4 x 10-10 |
1350 | a | 4.7 x 10-10 |
1477 | a | 2.8 x 10-9 |
1510 | a | 2.9 x 10-9 |