Table 2.
Tabulated information from characterisation of ThTi2O6 compositions, adopting the brannerite structure, targeting U5+ and U6+ incorporation with appropriate charge compensation (see Table 1). The secondary phases identified in the X-ray diffraction patterns and U oxidation states, as-determined by linear regression (LR) of the U L3 edge position, and linear combination fitting (LCF) and iterative target transformation factor analysis (ITFA) of HERFD U M4 edge XANES spectra, are also included.
| Target brannerite composition | ID | Target U ox. State | Secondary phases | U ox. state L3 edge LR | U ox. state M4 edge LCF |
U ox. state M4 edge ITFA |
|---|---|---|---|---|---|---|
| (Th0.90U0.10)Ti2O6 | 0.1U | – | TiO2, ThO2 | 5.0(2)+ | 4.93(12)+ | 4.91(6)+ |
| (Th0.95U0.05)Ti2O6 | 0.05U | – | TiO2, ThO2 | 5.0(2)+ | 4.91(12)+ | 4.89(6)+ |
| (Th0.85U0.10Ca0.05)Ti2O6 | 5Ca | 5+ | ThO2 | 5.0(2)+ | 4.98(9)+ | 4.96(6)+ |
| (Th0.90U0.05Ca0.05)Ti2O6 | 6Ca | 6+ | – | 5.0(2)+ | 5.06(9)+ | 5.04(6)+ |
| (Th0.80U0.10Gd0.10)Ti2O6 | 5Gd | 5+ | Trace TiO2/ThO2 | 4.9(2)+ | 5.06(7)+ | 5.04(6)+ |
| (Th0.85U0.05Gd0.10)Ti2O6 | 6Gd | 6+ | Trace TiO2 | 5.1(2)+ | 5.12(11)+ | 5.11(6)+ |
| (Th0.95U0.05)(Ti1.95Al0.05)O6 | 5Al | 5 + | ThO2 | 4.8(2)+ | 5.04(9)+ | 5.02(6)+ |
| (Th0.95U0.05)(Ti1.90Al0.10)O6 | 6Al | 6+ | ThO2 | 4.8(2)+ | 5.10(13)+ | 5.09(6)+ |
| (Th0.95U0.05)(Ti1.95Cr0.05)O6 | 5Cr | 5 + | ThO2 | 4.9(2)+ | 5.00(11)+ | 4.98(6)+ |
| (Th0.95U0.05)(Ti1.90Cr0.10)O6 | 6Cr | 6+ | ThO2 | 5.1(2)+ | 5.04(10)+ | 5.02(6)+ |