TDEP2023: Finite-temperature and anharmonic response properties of solids in theory and practice (A Marcus Wallenberg symposium)

We are pleased to announce the 5-day school and tutorial entitled "Finite-temperature and anharmonic response properties of solids in theory and practice - A Marcus Wallenberg Symposium" targeted at students and researchers in the field of first-principles-based materials simulations!

The goal of the school is to introduce state-of-the-art lattice dynamics methods for the simulation of thermodynamic, transport, and response properties of solids based on modern phonon theory. The following topics will be covered: Phonon theory including effective and self-consistent approaches, thermodynamics in different ensembles including quantum statistics, thermal transport for high- and low-thermal-conductivity materials in and beyond the single-mode relaxation time approximation, and many-body theory for the dynamical response of anharmonic solids in scattering experiments such as Neutron and Raman spectroscopy.

An emphasis will be placed on the connection of theory and application: The morning sessions are dedicated to our excellent lecturers (see below) who will provide thorough introductions to the fundamentals of each topic, and connect to more advanced aspects related to current research from there. In the afternoons, we introduce related implementations in the temperature-dependent effective potentials code (TDEP,, with hands-on tutorials to enable the participants to integrate the methods in their research. While a solid background in (ab initio) materials simulations is beneficial, the only prerequisite to attend the school is to be able to run single-point DFT or force field calculations to obtain forces for atomic structures. A list of key references for methods implement in the TDEP code is attached below. 

Installation instructions will be distributed prior to the event, further support will be provided on the first day of the school to ensure a working setup. Furthermore, the first day is dedicated to tooling and interfacing using python and software packages such as the Atomic Simulation Environment (ASE), so that participants with diverse backgrounds can take full advantage of the school. This extends to the different first-principles codes used in the community, as well as empirical and machine-learning force fields.

The school will be held August 21-25 at the Quality Hotel Ekoxen in Linköping, Sweden. Linköping is reachable via train, the local airport connecting to Amsterdam, Stockholm airport (2.5h away), or Copenhagen airport (3.5h away).

We strongly recommend participants to arrive on Sunday, August 20 and stay until Saturday, August 26 to take full advantage of the school. The school fee (see below) covers the full stay including hotel and food.

We are indebted to the Marcus Wallenberg Foundation for International Scientific Collaboration and the Swedish e-Science Research Centre (SeRC) for their generous support of this event.


  • Ivana Savic (King's College London)
  • Brent Fultz (Caltech)
  • Lucy Whalley (Northumbria University Newcastle)
  • Raffaello Bianco (University of Modena and Reggio Emilia)
  • Blazej Grabowski (University of Stuttgart)
  • Venkat Kapil (University of Cambridge)
  • David Broido (Boston College)
  • Michele Simoncelli (University of Cambridge)
  • Omer Yaffe (Weizmann Institute of Science)
  • Giorgia Fugallo (University of Nantes)


  • Roberta Farris (Catalan Institute of Nanoscience and Nanotechnology)
  • Aloïs Castellano (U Liege)
  • Jose Pedro Batista (U Liege)
  • Johan Klarbring (Imperial College London and Linköping University)
  • Ask Hjorth Larsen (DTU Copenhagen)


  • Aistė Miliūtė, Federal Institute for Materials Research and Testing (Bundesanstalt für Materialforschung und -prüfung)
  • Alberto M. Ruiz, Instituto de Ciencia Molecular (ICMol), University of Valencia, Spain
  • Aleksandar Živković, Utrecht University
  • Aloïs Castellano, University of Liège, Belgium
  • Annop Ektarawong, Department of Physics, Faculty of Science, Chulalongkorn University, Bangkok, Thailand 10330
  • Ask Hjorth Larsen, DTU Copenhagen
  • Blazej Grabowski, University of Stuttgart
  • Boburjon Mukhamedov, Linköping University
  • Brent Fultz, Caltech
  • Dylan Folkner, University of California, Davis
  • Erik Fransson, Chalmers
  • Ferenc Tasnadi, Linköping University
  • Florian Bock, Linköping University
  • Florian Knoop, Linköping University, Sweden
  • Florian Trybel, Linköping University
  • Frederik Vonhoff, Technical University Munich
  • Fredrik Eriksson, Chalmers
  • Giorgia Fugallo, University of Nantes
  • Igor Abrikosov, Linköping University
  • Ivana Savic, King's College London
  • Joana Cecibel, Bustamante Pineda Federal Institute for Materials Research and Testing (Bundesanstalt für Materialforschung und -prüfung)
  • Johan Klarbring, Linköping University, Sweden
  • Jose Pedro Batista, University of Liège, Belgium
  • Kazuki Morita, University of Pennsylvania
  • Kisung Kang, Fritz-Haber-Institut
  • Lucy Whalley, Northumbria University Newcastle
  • Lukas Legenstein, Institute of Solid State Physics, Graz University of Technology
  • Lukas Reicht, Graz University of Technology
  • Matthieu Verstraete, University of Liège, Belgium
  • Maxime Mignolet, University of Liège
  • Michele Simoncelli, University of Cambridge
  • Namrata Jaykhedkar, Comenius University
  • Nina Girotto, Institute of Physics, Zagreb, Croatia
  • Nina Strasser, Graz University of Technology
  • Niraj Singh, Linkoping University
  • Nityasagar Jena, Linköping University
  • Olle Hellman ,Weizmann Institute of Science, Israel
  • Omer Yaffe, Weizmann Institute of Science, Israel
  • Oscar Bulancea, Lindvall Linköping University
  • Paul Zeiger, Uppsala University
  • Petter Rosander, Chalmers University of Technology
  • Prakriti Kayastha, Northumbria University
  • Raffaello Bianco, University of Modena and Reggio Emilia
  • Roberta Farris, Catalan Institute of Nanoscience and Nanotechnology, Spain
  • Samuel Longo, ULiege
  • Samuel Poncé, UCLouvain
  • Sebastian Caicedo-Davila, Technical University of Munich
  • Sergei Simak, Linköping University
  • Shuo Zhao, The NOMAD Laboratory at the FHI of the Max-Planck-Gesellschaft and IRIS-Adlershof of the Humboldt-Universität zu Berlin
  • Sourav Dey, Institut de Ciència Molecular - ICMOL (UV)
  • Tran Quoc Dat, Linköping University
  • Utkarsh Singh, Linköping University
  • Venkat Kapil, University of Cambridge
  • Wenling Ren, TU-Darmstadt/TMM
  • Xia Liang, Imperial College London
  • Xiangzhou Zhu, TU Munich
  • Xingchen Shen, CRISMAT, Caen, France
  • YiXu Wang, Chair of Solid-state and Quantum Chemistry, Institute of Inorganic Chemistry, RWTH Aachen University
  • Zezhu Zeng, Institute of science and technology
  • Ziqi Yin, UNSWgroup photo of the participants in the TDEP summer school 2023Participants of the TDEP2023 summer school


  • Florian Knoop (Linköping University, Sweden)
  • Matthieu Verstraete (University of Liège, Belgium)
  • Olle Hellman (Weizmann Institute of Science, Israel)


Sunday August 20

Arrival, check in at the hotel, dinner

Monday August 21


  • Florian Knoop (LiU), Olle Hellman (Weizmann Institute): TDEP code installation support
  • Ask Hjorth Larsen (DTU Copenhagen): Tooling and interfacing with ASE


  • Ivana Savic (King's College London): Phonons and anharmonic properties, theory
  • Brent Fultz (Caltech): Phonons and anharmonic properties, experiment

Tuesday August 22


  • Lucy Whalley (Northumbria University Newcastle): Ab initio phonons
  • Raffaello Bianco (University of Modena and Reggio Emilia): Self-consistent phonons


Temperature-dependent effective potentials (TDEP) introduction, harmonic and anharmonic calculations, supercell convergence, spectral functions for Neutron spectroscopy.

Poster Session

Participants are invited to present and discuss their research.

Wednesday August 23


  • Blazej Grabowski (University of Stuttgart): Ab initio thermodynamics
  • Venkat Kapil (University of Cambridge): Quantum thermodynamics
  • David Broido (Boston College): Ab initio thermal transport


TDEP thermodynamics, self-consistent sampling, free energies and stability, thermal expansion

Social event

The exact activity will be announced later.

Thursday August 24


  • Michele Simoncelli (University of Cambridge): Wigner transport
  • Giorgia Fugallo (University of Nantes): 2D transport (probably shorter lecture)


Thermal conductivity in and beyond single-mode relaxation time approximation, spectral transport

Friday August 25


  • Omer Yaffe (Weizmann Institute of Science): Raman scattering and experimental response
  • Giorgia Fugallo (University of Nantes): Response theory


Raman and infrared response including anharmonic effects

Saturday August 26

Breakfast, checkout, farewell


Key references

TDEP method and efficient sampling including nuclear quantum effects
  • O. Hellman, I. A. Abrikosov, and S. I. Simak, Lattice Dynamics of Anharmonic Solids from First Principles, Phys Rev B 84, 180301 (2011).
  • O. Hellman, P. Steneteg, I. A. Abrikosov, and S. I. Simak, Temperature Dependent Effective Potential Method for Accurate Free Energy Calculations of Solids, Phys Rev B 87, 104111 (2013).
  • N. Shulumba, O. Hellman, and A. J. Minnich, Lattice Thermal Conductivity of Polyethylene Molecular Crystals from First-Principles Including Nuclear Quantum Effects, Phys Rev Lett 119, 185901 (2017).
Thermal expansion and pressure
  • D. S. Kim, O. Hellman, J. Herriman, H. L. Smith, J. Y. Y. Lin, N. Shulumba, J. L. Niedziela, C. W. Li, D. L. Abernathy, and B. Fultz, Nuclear Quantum Effect with Pure Anharmonicity and the Anomalous Thermal Expansion of Silicon, Proc National Acad Sci 115, 201707745 (2018).
  • D. Laniel et al., High-Pressure Synthesis of Seven Lanthanum Hydrides with a Significant Variability of Hydrogen Content, Nature Communications 13, 6987 (2022)
Thermal transport
  • A. H. Romero, E. K. U. Gross, M. J. Verstraete, and O. Hellman, Thermal Conductivity in PbTe from First Principles, Phys Rev B 91, 214310 (2015).
  • A. Dewandre, O. Hellman, S. Bhattacharya, A. H. Romero, G. K. H. Madsen, and M. J. Verstraete, Two-Step Phase Transition in SnSe and the Origins of Its High Power Factor from First Principles, Phys Rev Lett 117, 276601 (2016).
  • J. Klarbring, O. Hellman, I. A. Abrikosov, and S. I. Simak, Anharmonicity and Ultralow Thermal Conductivity in Lead-Free Halide Double Perovskites, Phys Rev Lett 125, 045701 (2020).
  • Đ. Dangić, O. Hellman, S. Fahy, and I. Savić, The Origin of the Lattice Thermal Conductivity Enhancement at the Ferroelectric Phase Transition in GeTe, Npj Comput Mater 7, 57 (2021).
  • D. S. Reig et al., Unraveling Heat Transport and Dissipation in Suspended MoSe2 from Bulk to Monolayer, Adv Mater 34, 2108352 (2022).
Temperature-dependent spectroscopy
  • M. Menahem, N. Benshalom, M. Asher, S. Aharon, R. Korobko, S. Safran, O. Hellman, and O. Yaffe, The Disorder Origin of Raman Scattering In Perovskites Single Crystals, Arxiv 2208.05563 (2022).
  • N. Benshalom, M. Asher, R. Jouclas, R. Korobko, G. Schweicher, J. Liu, Y. Geerts, O. Hellman, and O. Yaffe, Phonon-Phonon Interactions in the Polarizarion Dependence of Raman Scattering, Arxiv 2204.12528 (2022).
  • A. Cohen, T. M. Brenner, J. Klarbring, R. Sharma, D. H. Fabini, R. Korobko, P. K. Nayak, O. Hellman, and O. Yaffe, Diverging Expressions of Anharmonicity in Halide Perovskites, Adv Mater 2107932 (2022).
  • N. Benshalom, G. Reuveni, R. Korobko, O. Yaffe, and O. Hellman, Dielectric Response of Rock-Salt Crystals at Finite Temperatures from First Principles, Phys Rev Mater 6, 033607 (2022).


We acknowledge the generous support from our sponsors.