Role of Dispersive Interactions in Determining Structural Properties of Organic-Inorganic Halide Perovskites: Insights from First-Principles Calculations.
A microscopic picture of structure and bonding in organic-inorganic perovskites is imperative to understanding their remarkable semiconducting and photovoltaic properties. On the basis of a density functional theory treatment that includes both spin-orbit coupling and dispersive interactions, we provide detailed insight into the crystal binding of lead-halide perovskites and quantify the effect of different types of interactions on the structural properties. Our analysis reveals that cohesion in these materials is characterized by a variety of interactions that includes important contributions from both van der Waals interactions among the halide atoms and hydrogen bonding. We also assess the role of spin-orbit coupling and show that it causes slight changes in lead-halide bonding that do not significantly affect the lattice parameters. Our results establish that consideration of dispersive effects is essential for understanding the structure and bonding in organic-inorganic perovskites in general and for providing reliable theoretical predictions of structural parameters in particular.
Department of Materials and Interfaces, Weizmann Institute of Science, Rehovoth 76100, Israel.
David A
DA
Egger
Department of Materials and Interfaces, Weizmann Institute of Science, Rehovoth 76100, Israel.
Leeor
L
Kronik
density functional theory; dispersive interactions; lead−halide perovskites; photovoltaics; spin−orbit coupling; van der Waals interactions