1. Numerical stability and efficiency of response property calculations in density functional theory

    The goal of quantum-chemical calculations is the simulation of materials and molecules. In density-functional theory (DFT) the first step along this line is obtaining the electron density minimising an energy functional. However, since energies and the density are usually not very tractable quantities in an experimental setup, comparison to experiment …

    read more
  2. CECAM flagship workshop: Error control in first-principles modelling

    (Cross-post from our report published in the Psi-k blog)

    From 20th until 24th June 2022 I co-organised a workshop on the theme of Error control in first-principles modelling at the CECAM Headquarters in Lausanne (workshop website). For one week the workshop unified like-minded researchers from a range of communities, including …

    read more
  3. GdR REST Discussion meeting on Machine Learning

    Last week on 9th and 10th December 2021 I participated in the Discussion meeting on Machine Learning been organised by the French research group REST, which is centred around theoretical spectroscopy in solids and molecules. While most participants joined remotely I was fortunately able to travel to École Polytechnique in …

    read more
  4. A robust and efficient line search for self-consistent field iterations

    In an ongoing effort with Antoine Levitt our aim is to develop reliable density-functional theory (DFT) methods for computational materials design. Recently we looked into a strategy to automatically select the damping parameter for the self-consistent field iterations (SCF). Our adaptive damping approach is based on a theoretically sound quadratic …

    read more
  5. JuliaCon DFTK workshop: A mathematical look at electronic structure theory

    From 13th July till 30th July this year's JuliaCon finally took place virtually. The first week (13th till 27th) hosted a number of three-hour live-streamed sessions of workshops, while the "regular" conference with a number of prerecorded talks started on 28th.

    After my introductory talk to electronic structure theory and …

    read more
  6. Virtual materials design 2021: Black-box density-functional theory methods

    On 20th and 21st July 2021 the Virtual Materials Design 2021 CECAM workshop took place virtually. I was excited about this workshop and the opportunity to get in touch with researchers working on high-throughput computational materials design. While I am not actively working in this field the special requirements of …

    read more
  7. SSD Seminar: Accelerating the discovery of tomorrow's materials by robust and error-controlled simulations

    A couple of days ago, on 12th July, I was invited to present my research in the SSD Seminar Series of RWTH Aachen. Being part of the research training group on modern inverse problems as well as the School for Simulation and Data Science (SSD) the SSD seminars are interdisciplinary …

    read more
  8. Errors and uncertainty quantification in density-functional theory

    On 8th June I was invited to the seminar of the Uncertainty Quantification (UQ) group of Prof. Youssef Marzouk at MIT. Youssef and I planned to have this seminar since my involvement with MIT's CESMIX project last February (see also this blog article), but it took use quite some time …

    read more
  9. Talk at MATH4UQ seminar series at RWTH

    On 1st June I was invited to the MATH4UQ seminar series of the Mathematics of Uncertainty Quantification chair of Prof. Raul Tempone at RWTH Aachen University.

    Over the past months I got more and more interested in mathematical methods for uncertainty quantification (UQ) as an opportunity to estimate and understand …

    read more
  10. SIAM LA: Robust and efficient accelerated methods for density-functional theory

    Just one day after my talk at the SIAM Materials Science conference (blog article) I gave another talk at a SIAM meeting, this time at SIAM Linear Algebra. I was very much looking forward to participate in SIAM LA, firstly because it was the first time I attended this conference …

    read more
  11. SIAM MS: Using the density-functional toolkit to design black-box DFT methods

    After being moved by one year due to the pandemic, the last two weeks (from 17th to 28th May) the SIAM materials science conference finally took place in virtual form. Unfortunately this meant that the conference was scheduled in parallel to the SIAM Linear Algebra virtual conference, where I also …

    read more
  12. Thoughts on initial guess methods for DFT

    On Thursday I gave a brief talk in our weekly ACED differentiate group meeting about initial guess methods for starting self-consistent field calculations in methods such as density-functional theory. For preparing the talk I did a little digging into both the standard approaches used by many molecular and solid-state codes …

    read more
  13. A novel black-box preconditioning strategy for high-throughput density-functional theory

    A couple of weeks ago, from 15th to 19th March, I participated in the virtual annual meeting of the German Association of Applied Mathematics and Mechanics (GAMM). For me this meeting was the first time I presented my work to an audience of applied mathematicians with a broad background and …

    read more
  14. PostDoc position at Appl. & Comput. Mathematics lab, RWTH Aachen University

    This week I started my new position as a postdocotoral researcher at the Applied and Computational Mathematics (ACoM) research lab at RWTH Aachen University. The lab consists of two interdisciplinary research groups, namely the group of Prof. Dr. Manuel Torrilhon, who works on the mathematical modelling and simulation of technical …

    read more
  15. CESMIX TST meeting: DFTK.jl: A multidisciplinary Julia code for density-functional theory development

    These past two days I have participated in the Tri-Lab Support Team (TST) meeting of the CESMIX, the newly founded Center for the Exascale Simulation of Material Interfaces in Extreme Environments at the Massachusetts Institute of Technology. Within the next few years the idea of the CESMIX is to develop …

    read more
  16. High-throughput density-functional theory calculations: An interdisciplinary challenge

    Last Thursday I was invited to give a virtual talk at the Scientific Computing Seminar of working group of Prof. Nicolas Gauger at TU Kaiserslautern. Since the research in Prof. Gauger's group mostly concerns topics which are not directly related to electronic structure theory and density-functional theory (DFT), I chose …

    read more
  17. Black-box inhomogeneous preconditioning for self-consistent field iterations in density-functional theory

    For the past half a year or so Antoine Levitt and myself have been looking at a particular tricky busyness for solid-state density-functional theory (DFT) calculations, namely how to design efficient self-consistent field (SCF) schemes for large inhomogeneous systems. I have already previously reported on this matter in a short …

    read more
  18. A posteriori error estimation for the non-self-consistent Kohn-Sham equations

    After about a year of work on the density-functional toolkit (DFTK) we finally started using the code for some new science. Given the mathematics background of the CERMICS the first two DFTK-related articles were not so much about large-scale applications, but rather deal some fundamental questions of Kohn-Sham density-functional theory …

    read more
  19. PostDoc position at CERMICS / Sorbonne Université

    Last week I started my new position as a postdoctoral fellow at the MATHERIALS team of the Centre d'Enseignement et de Recherche en Mathématiques et Calcul Scientifique (CERMICS) laboratory and Inria Paris with an additional affiliation to the Institut des Sciences du Calcul et des Données at Sorbonne Université. As …

    read more