Electronic and Optical Properties of Sodium Niobate: A Density Functional Theory Study

Figure 4

NaNbO₃ dielectric functions calculated using different exchange-correlation potentials. The real (orange) and imaginary (green) parts of the dielectric functions for (a) the conventional PBE functional of Perdew et al. [16], (b) the PBEsol functional revised for solids [18], (c) the AM05 functional [17], and (d) the PBE0 hybrid functional [19].