646 citations · 1.7k across the 20 of their papers we have counts for
20 papers
Simulating the influence of stoichiometry on the spectral emissivity of MoSi thin films
Zahra Golsanamlou, Arseniy Baskakov, Robbert van de Kruijs +4
In this work, we simulate the spectral emissivity of various stoichiometric crystal phases of MoSi compounds using density functional perturbation theory. The dielectric fu…
Smooth Overlap of Spin Orientations: Machine Learning Exchange Fields for Ab-initio Spin Dynamics
Yuqiang Gao, Menno Bokdam, Paul J. Kelly
We add the magnetic degrees of freedom to the widely used Gaussian Approximation Potential of machine learning (ML) and present a model that describes the potential energy surface…
Tuning Einstein Oscillator Frequencies of Cation Rattlers: A Molecular Dynamics Study of the Lattice Thermal Conductivity of CsPbBr
Jonathan Lahnsteiner, Max Rang, Menno Bokdam
The pure CsPbBr perovskite is an archetypal example of a strongly anharmonic crystal that poses a major challenge for computational methods to describe its thermodynamic proper…
Phase transitions of LaMnO and SrRuO from DFT + U based machine learning force fields simulations
Thies Jansen, Geert Brocks, Menno Bokdam
Perovskite oxides are known to exhibit many magnetic, electronic and structural phases as function of doping and temperature. These materials are theoretically frequently investiga…
Dynamic Distortions of Quasi-2D Ruddlesden-Popper Perovskites at Elevated Temperatures: Influence on Thermal and Electronic Properties
Raisa-Ioana Biega, Menno Bokdam, Kai Herrmann +5
Ruddlesden-Popper hybrid halide perovskite are quasi-two-dimensional materials with a layered structure and structural dynamics that are determined by the interplay between the org…
Exploring librational pathways with on-the-fly machine-learning force fields: Methylammonium molecules in MAPbX (X=I, Br, Cl) perovskites
Menno Bokdam, Jonathan Lahnsteiner, D. D. Sarma
Two seemingly similar crystal structures of the low-temperature (~100 K) MAPbX (X=I,Br,Cl) perovskites, but with different relative Methylammonium (MA) ordering, have appeared…
Optical and excitonic properties of transition metal oxide perovskites by the Bethe-Salpeter equation
Lorenzo Varrassi, Peitao Liu, Zeynep Ergönenc Yavas +3
We present a systematic investigation of the role and importance of excitonic effects on the optical properties of transitions metal oxide perovskites. A representative set of four…
Anharmonic lattice dynamics in large thermodynamic ensembles with machine-learning force fields: CsPbBr a phonon-liquid with Cs rattlers
Jonathan Lahnsteiner, Menno Bokdam
The phonon dispersion relations of crystal lattices can often be well-described with the harmonic approximation. However, when the potential energy landscape exhibits more anharmon…
Long-range order imposed by short-range interactions in methylammonium lead iodide: Comparing point-dipole models to machine-learning force fields
Jonathan Lahnsteiner, Ryosuke Jinnouchi, Menno Bokdam
The crystal structure of the MAPbI hybrid perovskite forms an intricate electrostatic puzzle with different ordering patterns of the MA molecules at elevated temperatures. For…
Phase transitions of hybrid perovskites simulated by machine-learning force fields trained on-the-fly with Bayesian inference
Ryosuke Jinnouchi, Jonathan Lahnsteiner, Ferenc Karsai +2
Realistic finite temperature simulations of matter are a formidable challenge for first principles methods. Long simulation times and large length scales are required, demanding ye…
The Finite Temperature Structure of the MAPbI3 Perovskite: Comparing Density Functional Approximations and Force Fields to Experiment
Jonathan Lahnsteiner, Georg Kresse, Jurn Heinen +1
Determining the finite temperature structure of the hybrid perovskite MAPbI3 is a challenge for both experimental and theoretical methods. A very powerful computational method that…
Assessing density functionals using many body theory for hybrid perovskites
Menno Bokdam, Jonathan Lahnsteiner, Benjamin Ramberger +2
Which density functional is the "best" for structure simulations of a particular material? A concise, first principles, approach to answer this question is presented. The random ph…
Room temperature dynamic correlation between methylammonium molecules in lead-iodine based perovskites: An ab-initio molecular dynamics perspective
Jonathan Lahnsteiner, Georg Kresse, Abhinav Kumar +3
The high efficiency of lead organo-metal-halide perovskite solar cells has raised many questions about the role of the methylammonium (MA) molecules in the Pb-I framework. Experime…
invariance of Germanene on MoS from first principles
Taher Amlaki, Menno Bokdam, Paul J. Kelly
We present a low energy Hamiltonian generalized to describe how the energy bands of germanene () are modified by interaction with a substrate or a capping layer.…
Role of Polar Phonons in the Photo Excited State of Metal Halide Perovskites
Menno Bokdam, Tobias Sander, Alessandro Stroppa +4
The development of high efficiency perovskite solar cells has sparked a multitude of measurements on the optical properties of these materials. For the most studied methylammonium(…
Large potential steps at weakly interacting metal-insulator interfaces
Menno Bokdam, Geert Brocks, Paul J. Kelly
Potential steps exceeding 1 eV are regularly formed at metal|insulator interfaces, even when the interaction between the materials at the interface is weak physisorption. From firs…
Schottky barriers at hexagonal boron nitride/metal interfaces: a first principles study
Menno Bokdam, Geert Brocks, Mikhail I. Katsnelson +1
The formation of a Schottky barrier at the interface between a metal and hexagonal boron nitride (h-BN) is studied using density functional theory. For metals whose work functions…
Band gaps in incommensurable graphene on hexagonal boron nitride
Menno Bokdam, Taher Amlaki, Geert Brocks +1
Devising ways of opening a band gap in graphene to make charge-carrier masses finite is essential for many applications. Recent experiments with graphene on hexagonal boron nitride…
Field effect doping of graphene in metal|dielectric|graphene heterostructures: a model based upon first-principles calculations
Menno Bokdam, Petr A. Khomyakov, Geert Brocks +1
We study how the Fermi energy of a graphene monolayer separated from a conducting substrate by a dielectric spacer depends on the properties of the substrate and on an applied volt…
Electrostatic doping of graphene through ultrathin hexagonal boron nitride films
Menno Bokdam, Petr A. Khomyakov, Geert Brocks +2
When combined with graphene, hexagonal boron nitride (h-BN) is an ideal substrate and gate dielectric with which to build metalh-BN|graphene field-effect devices. We use first-prin…