Geometric optimisation and structural properties of organic−inorganic halide perovskites from van der Waals density functional theory calculations

Abstract

Organic–inorganic hybrid perovskites have attracted extensive attention in the photovoltaic field due to their unique photoelectric properties and low production costs. Using the density functional theory-based first-principles calculations, we reported the geometric optimisation and structural properties of halide perovskites using van der Waals density functional theory calculations. The strongly constrained and appropriately normed (SCAN) meta-GGA with the revised Vydrov-van Voorhis no-local correlation functional (SCAN + rVV10) are promising van der Waals density functional for solving van der Waals (vdW) interaction problems that many non-empirical semilocal functionals fail to include. We found the optimised structure parameters of halide perovskites based on the SCAN + rVV10 functionals are much closer to the experimental results than other functional including PBE and PBE + vdW-TS functionals, which provides the fundamental aspect for the theoretical calculations of surfaces, interfaces, optical properties, and structure-properties relationship.