Emergence of hidden phases of methylammonium lead-iodide (CHNHPbI) upon compression
arXiv:1806.05858 · doi:10.1103/PhysRevMaterials.2.085201
Abstract
We perform a thorough structural search with the minima hopping method (MHM) to explore low-energy structures of methylammonium lead iodide. By combining the MHM with a forcefield, we efficiently screen vast portions of the configurational space with large simulation cells containing up to 96 atoms. Our search reveals two structures of methylammonium iodide perovskite (MAPI) that are substantially lower in energy than the well-studied experimentally observed low-temperature orthorhombic phase according to density functional calculations. Both structures have not yet been reported in the literature for MAPI, but our results show that they could emerge as thermodynamically stable phases via compression at low temperatures. In terms of the electronic properties, the two phases exhibit larger band gaps than the standard perovskite-type structures. Hence, pressure induced phase selection at technologically achievable pressures (i.e., via thin-film strain) is a route towards the synthesis of several MAPI polymorph with variable band gaps.
References in corpus (15)
- Restoring the density-gradient expansion for exchange in solids and surfaces
- Generalized gradient approximation for solids and their surfaces
- Atomistic origins of high-performance in hybrid halide perovskite solar cells
- Relativistic Solar Cells
- Steric engineering of metal-halide perovskites with tunable optical band gaps
- Revealing the role of organic cations in hybrid halide perovskites CH3NH3PbI3
- Lattice dynamics and vibrational spectra of the orthorhombic, tetragonal and cubic phases of methylammonium lead iodide
- Crystal structure prediction using the Minima Hopping method
- A fingerprint based metric for measuring similarities of crystalline structures
- High-pressure behavior of methylammonium lead iodide (MAPbI3) hybrid perovskite
- Assessing density functionals using many body theory for hybrid perovskites
- Atomic structure of metal-halide perovskites from first principles: The chicken-and-egg paradox of the organic-inorganic interaction
- Elemental Phosphorus: structural and superconducting phase diagram under pressure
- Room temperature dynamic correlation between methylammonium molecules in lead-iodine based perovskites: An ab-initio molecular dynamics perspective
- Layered structures of organic/inorganic hybrid halide perovskites