Publications

@article{Verdi2021,

title = {Thermal transport and phase transitions of zirconia by on-the-fly machine-learned interatomic potentials},

author = {Carla Verdi and Ferenc Karsai and Peitao Liu and Ryosuke Jinnouchi and Georg Kresse},

doi = {10.1038/s41524-021-00630-5},

year  = {2021},

date = {2021-09-30},

urldate = {2021-09-30},

journal = {npj Computational Materials},

volume = {7},

pages = {156},

publisher = {Springer Science and Business Media LLC},

abstract = {Machine-learned interatomic potentials enable realistic finite temperature calculations of complex materials properties with first-principles accuracy. It is not yet clear, however, how accurately they describe anharmonic properties, which are crucial for predicting the lattice thermal conductivity and phase transitions in solids and, thus, shape their technological applications. Here we employ a recently developed on-the-fly learning technique based on molecular dynamics and Bayesian inference in order to generate an interatomic potential capable to describe the thermodynamic properties of zirconia, an important transition metal oxide. This machine-learned potential accurately captures the temperature-induced phase transitions below the melting point. We further showcase the predictive power of the potential by calculating the heat transport on the basis of Green–Kubo theory, which allows to account for anharmonic effects to all orders. This study indicates that machine-learned potentials trained on the fly offer a routine solution for accurate and efficient simulations of the thermodynamic properties of a vast class of anharmonic materials.},

keywords = {P03},

pubstate = {published},

tppubtype = {article}

}

@article{Franceschi2021,

title = {Two-dimensional surface phase diagram of a multicomponent perovskite oxide: La_{0.8}Sr_{0.2}MnO_{3} (110)},

author = {Giada Franceschi and Michael Schmid and Ulrike Diebold and Michele Riva},

doi = {10.1103/physrevmaterials.5.l092401},

year  = {2021},

date = {2021-09-24},

urldate = {2021-09-24},

journal = {Physical Review Materials},

volume = {5},

number = {9},

pages = {L092401},

publisher = {American Physical Society (APS)},

abstract = {The many surface reconstructions of (110)-oriented lanthanum strontium manganite (\textbf{La_{0.8}Sr_{0.2}MnO}3}}, LSMO) were followed as a function of the oxygen chemical potential (\textit{\textbf{μ}_{O}}) and the surface cation composition. Decreasing \textit{\textbf{μ}_{O}} causes Mn to migrate across the surface, enforcing phase separation into \textit{\textbf{A}}-site-rich areas and a variety of composition-related, structurally diverse \textit{\textbf{B}}-site-rich reconstructions. The composition of these phase-separated structures was quantified with scanning tunneling microscopy, and these results were used to build a two-dimensional phase diagram of the LSMO(110) equilibrium surface structures.},

keywords = {P02},

pubstate = {published},

tppubtype = {article}

}

@article{Zeininger2021,

title = {Single-Particle Catalysis: Revealing Intraparticle Pacemakers in Catalytic H2 Oxidation on Rh},

author = {Johannes Zeininger and Yuri Suchorski and Maximilian Raab and Sebastian Buhr and Henrik Grönbeck and Günther Rupprechter},

doi = {10.1021/acscatal.1c02384},

year  = {2021},

date = {2021-07-27},

urldate = {2021-07-27},

journal = {ACS Catalysis},

volume = {11},

number = {15},

pages = {10020--10027},

publisher = {American Chemical Society (ACS)},

abstract = {Self-sustained oscillations in H_{2} oxidation on a Rh nanotip mimicking a single catalytic nanoparticle were studied by in situ field emission microscopy (FEM). The observed spatio-temporal oscillations result from the coupling of subsurface oxide formation/depletion with reaction front propagation. An original sophisticated method for tracking kinetic transition points allowed the identification of local pacemakers, initiating kinetic transitions and the nucleation of reaction fronts, with much higher temporal resolution than conventional processing of FEM video files provides. The pacemakers turned out to be specific surface atomic configurations at the border between strongly corrugated Rh{973} regions and adjacent relatively flat terraces. These structural ensembles are crucial for reactivity: while the corrugated region allows sufficient oxygen incorporation under the Rh surface, the flat terrace provides sufficient hydrogen supply required for the kinetic transition, highlighting the importance of interfacet communication. The experimental observations are complemented by mean-field microkinetic modeling. The insights into the initiation and propagation of kinetic transitions on a single catalytic nanoparticle demonstrate how in situ monitoring of an ongoing reaction on individual nanofacets can single out active configurations, especially when combined with atomically resolving the nanoparticle surface by field ion microscopy (FIM).},

keywords = {P08, TACO-associated},

pubstate = {published},

tppubtype = {article}

}