Table 7. Comparison of Ionic (Low-Frequency) and Electronic (High-Frequency) Components (εij(0) and εij(∞), Respectively) of the Relative Dielectric Permittivity Tensor εr of R-TiO2, Obtained Using Three Cutoff Energies in Combination with the PBEsol and Three PAW Potentials Ti_std, Ti_pv, and Ti_sva.
| PAW potential | cutoff energy/eV | εij(0) |
εij(∞) |
εr | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
| εxx(0) | εyy(0) | εzz(0) | εr(0) | εxx(∞) | εyy(∞) | εzz(∞) | εr(∞) | εr(0) + εr(∞) | ||
| R-TiO2 | ||||||||||
| Ti_std | 520.0 | 124.0 | 124.0 | 163.0 | 137.0 | 8.0 | 8.0 | 9.6 | 8.5 | 145.5 |
| 600.0 | 123.4 | 123.4 | 162.3 | 136.4 | 8.0 | 8.0 | 9.6 | 8.5 | 144.9 | |
| 700.0 | 122.9 | 122.9 | 161.3 | 135.7 | 8.0 | 8.0 | 9.6 | 8.5 | 144.2 | |
| Ti_pv | 520.0 | 354.1 | 354.1 | 1135.2 | 614.5 | 7.6 | 7.6 | 9.1 | 8.1 | 622.6 |
| 600.0 | 366.0 | 366.0 | 1257.8 | 663.3 | 7.6 | 7.6 | 9.1 | 8.1 | 671.3 | |
| 700.0 | 370.3 | 370.3 | 1327.0 | 689.2 | 7.6 | 7.6 | 9.1 | 8.1 | 697.3 | |
| Ti_sv | 520.0 | 296.2 | 296.2 | 732.9 | 441.8 | 7.5 | 7.5 | 8.9 | 8.0 | 449.9 |
| 600.0 | 309.1 | 309.1 | 799.3 | 472.5 | 7.5 | 7.5 | 8.9 | 8.0 | 480.5 | |
| 700.0 | 327.1 | 327.1 | 966.8 | 540.3 | 7.5 | 7.5 | 8.9 | 7.9 | 548.2 | |
| expt.14c | 111 | 111 | 257 | 159.7 | ||||||
| expt.25 | 84.69 | 84.69 | 152.97 | 107.45 | 5.96 | 5.96 | 7.16 | 6.36 | 113.81 | |
| expt.85 | 84.02 | 84.02 | 153.83 | 107.29 | 5.91 | 5.91 | 7.19 | 6.34 | 113.63 | |
| expt.89 | 81.8 | 81.8 | 167.1 | 110.23 | 6.00 | 6.00 | 7.80 | 6.60 | 116.83 | |
| expt.25 | 87.0 | 87.0 | 163.0 | 112.33 | 6.12 | 6.12 | 7.63 | 6.62 | 118.96 | |
| expt.25 | 89.8 | 89.8 | 166.7 | 115.43 | 6.32 | 6.32 | 7.80 | 6.81 | 122.25 | |
| expt.25 | 86 | 86 | 170 | 114.00 | 6.84 | 6.84 | 8.43 | 7.37 | 121.37 | |
| A-TiO2 | ||||||||||
| Ti_std | 700 | 44.1 | 44.1 | 21.2 | 36.4 | 7.4 | 7.4 | 6.7 | 7.1 | 43.6 |
| Ti_pv | 700 | 54.6 | 54.6 | 23.6 | 44.3 | 7.0 | 7.0 | 6.4 | 6.8 | 51.1 |
| Ti_sv | 700 | 52.4 | 52.4 | 23.3 | 42.7 | 6.9 | 6.9 | 6.3 | 6.7 | 49.4 |
| expt.92 | 45.1 | 45.1 | 22.7 | 37.6 | 5.8 | 5.8 | 5.4 | 5.7 | 43.3 | |
| B-TiO2 | ||||||||||
| Ti_std | 700 | 48.2 | 50.7 | 45.0 | 49.4 | 7.6 | 8.0 | 7.4 | 7.7 | 57.2 |
| Ti_pv | 700 | 52.8 | 70.1 | 47.3 | 56.7 | 7.0 | 7.7 | 7.0 | 7.2 | 64.0 |
| Ti_sv | 700 | 52.4 | 68.6 | 47.9 | 56.3 | 6.9 | 7.6 | 6.9 | 7.1 | 63.4 |
| Ref (23)b | 64.1 | 86.7 | 55.2 | 68.7 | 6.8 | 7.5 | 6.8 | 7.0 | 75.7 | |
| Ref (23)b | 50.2 | 58.2 | 50.0 | 52.8 | 7.0 | 7.5 | 6.9 | 7.1 | 59.9 | |
| expt.97,98 | 93 | 78 | ||||||||
a
Both low- and room-temperature experimental values of εr reported by various authors are included.
b
Reported at the LDA and GGA levels, using Quantum Expresso software.
c
Low-temperature data refer T = 1.6 K.