Table 8. Rietveld Refinements Results for Tb-Doped and Pure Specimens, As Synthesized (AS) and Heat Treated (HT), Using Tetragonal Symmetry, S.G. I4/mmma.
| Tb:AS | Tb:HT | pure:HT | |
|---|---|---|---|
| a | 8.1480 (5) | 8.1633 (1) | 8.1631 (1) |
| c | 11.5800 (15) | 11.5537 (2) | 11.5515 (2) |
| c/a√2 | 1.0049 (10) | 1.0008 (1) | 1.0006 (1) |
| K (Uiso) | 0.02457 (120) | 0.01914 (41) | 0.01902 (35) |
| Y1 (Uiso) | 0.00716 (47) | 0.00379 (24) | 0.00404 (20) |
| Y2 (Uiso) | 0.00364 (66) | 0.00522 (52) | 0.00514 (44) |
| F1 (Uiso) | 0.01500 (127) | 0.00766 (45) | 0.00691 (39) |
| F2 (Uiso) | 0.00009 (100) | 0.00904 (150) | 0.0095 (108) |
| F3 (Uiso) | 0.01432 (323) | 0.00550 (257) | 0.00367 (162) |
| xY1 | 0.23860 (19) | 0.24074 (12) | 0.24076 (11) |
| zY2 | 0.24408 (41) | 0.23992 (25) | 0.23970 (21) |
| xF1 | 0.22473 (81) | 0.22633 (81) | 0.22642 (66) |
| zF1 | 0.12674 (103) | 0.11036 (76) | 0.10972 (60) |
| xF2 | 0.17052 (83) | 0.16399 (114) | 0.16235 (77) |
| zF2 | 0.16543 (85) | 0.16501 (84) | 0.16459 (69) |
| xF3 | 0.30175 (149) | 0.33533 (202) | 0.33911 (118) |
| Rwp | 6.4 | 4.6 | 7.0 |
a
The lattice constants are expressed in Å, the Debye–Waller factors in Å2, and the Rietveld statistics factors in percent.