First principle study on the Structural and Electronic Properties of Lead-Free Double Halide Perovskite Cs2InSbCl6
The structural and electronic characteristics of Cs2InSbCl6 were investigated using first
principle density functional theory (DFT) within local density approximation (LDA) and
generalized gradient approximation (GGA) as implemented in the Quantum ESPRESSO
package. A supercell with 40 atoms was used in carrying out the calculations, using the
optimized lattice parameters of the Cs2InSbCl6 (a = b = c =11.342 Ǻ). The findings revealed
that Cs2InSbCl6 is a direct band gap material with gaps of 0.74 eV and 0.99 eV for LDA/PZ
and GGA/PBE respectively, in which the GGA/PBE gap shows consistency within the
literature range. The calculated densities of states highlight the contributions of the constituent
atoms within the valence and the conduction bands.