Abstract
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.
Original language | English |
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Pages (from-to) | 2728-2733 |
Number of pages | 6 |
Journal | Journal of Physical Chemistry Letters |
Volume | 5 |
Issue number | 15 |
DOIs | |
State | Published - 7 Aug 2014 |
Externally published | Yes |
Keywords
- density functional theory
- dispersive interactions
- lead-halide perovskites
- photovoltaics
- spin-orbit coupling
- van der Waals interactions