Regensburg 2013 – wissenschaftliches Programm

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TT: Fachverband Tiefe Temperaturen

TT 10: Focused Session: Frontiers of Electronic Structure Theory 1 (jointly with HL and O)

TT 10.2: Vortrag

Montag, 11. März 2013, 11:00–11:15, H36

Fast screening of perovskites’ phase stability using AIDA, a materials’ informatics platform for materials design and discovery — •Giovanni Pizzi¹, Andrea Cepellotti¹, Boris Kozinsky², Marco Fornari³, and Nicola Marzari¹ — ¹Theory and Simulation of Materials, EPFL (CH) — ²Robert Bosch LCC Research and Technology Center, Cambridge (USA) — ³Dept. of Physics, Central Michigan University (USA)

Many perovskite systems display a high-temperature cubic phase with zero net polarization, whose microscopic nature is still debated. We perform a systematic study of this phase for representative ABO₃ perovskites, showing that there is not a unique microscopic model for it. Some systems are consistent with a displacive or an order/disorder model; others can sustain a stable displacement pattern of B-site cations in supercells, preserving zero net polarization. In such high-throughput searches, a key challenge is the need of a “materials’ informatics” infrastructure to automatically prepare, execute and monitor workflows of calculations for large classes of materials, and then retrieve, store and analyze the results. To this aim, we are developing an open-source platform for high–throughput (AIDA–“Automated Infrastructure and Database for Ab-initio design”). Using AIDA free-energy workflows, we studied the phase stability of BaTiO₃, evaluating the critical temperatures between the cubic, tetragonal, orthorhombic, and rhombohedral phases.