Table 1 Optimized structural parameters, calculated tolerance factor (τG), formation energy (eV), and cohesive energy (eV/atom) for A2LiBiI6 (A=Na, K, Rb)
Compound | Lattice constant a = b = c (Å) | Volume (Å)3 | ρ (g/cm3) | Band gap Eg (eV) GGA-PBE | Band gap Eg (eV) YS-PBE0 | Tolerance factor (τG) | Octahedral factor (μ) | ΔHf (eV/formula unit) |
|---|---|---|---|---|---|---|---|---|
Na2LiBiI6 | 11.997 | 1726.921 | 0.984 | 1.891 | 1.896 | 0.820 | 0.407 | −1.45 |
K2LiBiI6 | 12.129 | 1784.393 | 0.983 | 1.989 | 2.004 | 0.877 | 0.407 | −1.14 |
Rb2LiBiI6 | 12.189 | 1811.180 | 1.053 | 2.014 | 2.038 | 0.896 | 0.407 | −1.07 |
Cs2AgBiBr6 | 11.271 | -- | -- | 2.1937 (exp)/ 2.06 (theo) | -- | -- | -- | -- |
Cs2NaBiCl6 | 11.036 | -- | -- | -- | -- | -- | -- |
