The Psi-k Community

MISSION: Psi-k is a Europe-based, worldwide network of researchers working on the advancement of first-principles computational materials science. Its mission is to develop fundamental theory, algorithms, and computer codes in order to understand, predict, and design materials properties and functions. Theoretical condensed matter physics, quantum chemistry, thermodynamics, and statistical mechanics form its scientific core. Applications encompass inorganic, organic and bio-materials, and cover a whole range of diverse scientific, engineering, and industrial endeavours. Key activities of Psi-k are the organization of conferences, workshops, tutorials and training schools as well as the dissemination of scientific thinking in society.

Psi-k is a bottom-up researchers’ network, established in 1994, to build strength and cooperation in the field of computational electronic structure. Psi-k activities are coordinated by a Board of Trustees, a Scientific Advisory Committee, and 16 Working Groups. These activities encompass the organization or co-sponsoring of ~30 workshops, conferences, schools or tutorials every year, an annual research conference jointly with CECAM, and a major conference covering the entire field every 5 years.

In addition, Psi-k produces a regular newsletter with extensive scientific highlights, and allows researchers to advertise job openings, events, and other topics of mutual interest through its 5000+ members mailing list.

This new website — introduced in  2015 to replace a venerable old site that provided sterling service over many years — offers a much more flexible modern design and functionality and it is to be hoped that it will provide even more stimulus for collaboration and cooperation amongst its members. Instructions regarding how to use it are here.

Psi-k is a registered charity and can only continue to operate thanks to the contributions from our member organisations and institutions. If you would like to make a donation to Psi-k please contact us.

Report on Green’s function methods: the next generation


The main objective of the workshop “Green’s function methods: the next generation”, arrived at its 4-th edition, is to bring together an interdisciplinary audience of researchers dealing with Green’s functions methods and electron correlation. Both fundamental developments and high-end applications are targeted, together with discussions on numerical implementations and their current limitations.

Green’s functions have always played a prominent role in many-body physics. In particular the one-body Green’s function (GF) delivers a wealth of information about a physical system, such as ground-state energy, excitation energies, densities and other measurable quantities. Therefore the development of approximate methods to calculate the one-body GF has been an active research topic in many-body physics since the 60’s, and many routes have been explored in order to find increasingly accurate GFs. A very popular class of methods is based on the iterative solution of an integral equation for the GF containing an effective potential, the so-called self-energy, which needs to be approximated. The well-known GW approximation belongs to this class; this approximation is the method of choice for calculating band structures, but it also shows several shortcomings, such as the wrong description of satellites in photo-emission spectra, in particular in so-called strongly-correlated materials. Therefore more refined levels of approximations are needed to keep the pace with the advances made in experiment. Recently much progress has been made in this direction both by going beyond standard methods and also exploring completely novel routes to calculate GF. A new wave of original ideas, understanding, and solutions, has pervaded the field and was represented in the present workshop.

Continue reading Report on Green’s function methods: the next generation

What about U in nanoscale systems?

Workshop Report
What about U in nanoscale systems?

ZCAM/BIFI, Zaragoza, Spain, May 21-24 2019

Organizers: David Jacob (UPV/EHU, San Sebastian), Massimo Capone (SISSA, Trieste), Silke Biermann (Ecole Polytechnique, Paris)

Local Organizers: Beatriz Antoli, Adrian Velazquez-Campoy (ZCAM, BIFI, Zaragoza)

The Workshop “What about U in nanoscale systems?” took place at the CECAM node in Zaragoza from May 21 to May 24 2019. It followed the format of previous What about U editions, bringing together colleagues from different communities (including experimentalists) and providing ample discussion time. The new aspect this year was the focus on nanoscale systems, while also general aspects of correlations found their place. Continue reading What about U in nanoscale systems?

2020-21 Psi-k Event Application

Herewith we solicit for proposals for activities in the field of electronic-structure theory and calculations to be held between 1 April 2020 and 31 March 2021, to be funded (in full/partially) by the Psi-k Network and Charity.

Please note: for this year only events that take place between mid-August and mid-October 2020 will NOT be considered for funding to avoid a clash with the Psi-k Conference that will take place in Lausanne, September 2020

Psi-k has introduced a two-step application process, to improve planning and avoid duplication of efforts.

First, a pre-proposal should be submitted by Friday 30 August 2019 (midnight CEST), describing the planned event. The working groups ( will either approve this pre-proposal for full submission, reject it, or suggest a merger between different activities – you are very welcome to contact the working group leaders or members beforehand.

Feedback will be provided the week commencing Monday 30 September 2019. Pre-proposals that have been approved, or mergers that have been successfully negotiated, will then have to submit a full proposal by Friday 1 November 2019. These proposals will be evaluated and approved with full or partial funding, or declined, at the Psi-k meeting of the Scientific Advisory Committee ( and working group leaders, on Friday 29 November 2019.

Psi-k typically funds schools (1-2 weeks), workshops (2-3 days), international conferences (2-5 days), and code/method tutorials (3 days-1 week), with a focus on electronic- structure methods, developments, and applications. Its mission statement is available at Typical funding is of the order of 4,000/8,000/12,000 €, depending on size and duration (as a guideline, 30 €/expected participant/day); Psi-k funds around 25-35 activities for every call (see here for the 2019-20 activities).

The evaluation of the pre-proposals and full proposals will be based on:

  1. the scientific quality of the proposal,
  2. its intellectual diversity and inclusiveness,
  3. the scientific merit of the organizers, and
  4. appropriateness of budget, while of course
  5. responding to the Psi-k mission statement.

This form (as one single PDF document) should be uploaded by the deadline of Friday 30 August 2019 (midnight CEST) at

Please name your file as follows:
(example: Jones_Fundamentals_of_QM_April2020.pdf).

Pre-proposal WORD document
Pre-proposal PDF document

Reporting: The organizers of successful proposals must deliver a report of the event, and preferably provide access to the presentation materials through the Psi-k website.

With best regards,

Nicola Marzari
Psi-k Chairman

Peter Dederichs
Psi-k Financial Officer

Workshop on Advances in Electron Spectroscopy – Experiment and Theory, April 14-17, 2019, Dresden

The workshop aimed at bringing together experimentalists and theorists dealing with electronic structure investigations in correlated materials. Strongly correlated materials are notoriously difficult to describe theoretically due to the competing energy scales and emerging phenomena (like the Kondo effect) coming into play while at the same time experiments can provide a wealth of results whose interpretation often proves overwhelmingly challenging. It is therefore pivotal to bring together physicists investigating such materials theoretically or experimentally, to provide a common platform for discussions and encourage mutual insight into problems and results. This workshop aimed at exactly such an information exchange. Experimentally, recent advances in angle- and spin-resolved photoemission spectroscopy and scanning tunneling spectroscopy are leading examples for providing information about the materials’ electronic structure while cutting-edge density functional theory and dynamical mean field theory have developed into powerful tools for electronic structure calculations. Strongly correlated materials of interest ranged from transition metal compounds to f-electron systems. Of particular interest were also topological materials. Continue reading Workshop on Advances in Electron Spectroscopy – Experiment and Theory, April 14-17, 2019, Dresden

Developing High-Dimensional Potential Energy Surfaces: From the Gas Phase to Materials

Workshop Göttingen 2019

The workshop took place in April 2019 in Göttingen and brought together leading researchers who develop and apply machine learning methods with the common goal of determining the fundamental properties of “small” molecules, biomolecules, and materials. These properties include high-dimensional potential energy surfaces, atomic densities, and molecular properties, such as dipole moments and polarizabilities. Communities in the areas of materials, biomolecules, gas-phase molecules and complexes have formed over the past ten or so years and a major objective of the workshop was to bring these communities together to hear and learn from each other’s experience.

Read the full report

15th ETSF Young Researchers’ Meeting

In 2018, the ​ ETSF Young Researchers’ Meeting​ took place in Hamburg, Germany. The hottest summer in the history of Hamburg, the well prepared Center for Free Electron Laser Science (CFEL) and more than sixty motivated researcher built the perfect frame
for a stimulating week full of science.

The Young Researchers’ Meeting (YRM) of the European Theoretical Spectroscopy Facility (ETSF) is an annual conference organized and attended exclusively by researchers without permanent position that work on state-of-the-art theoretical and computational methods for the study of electronic and optical properties of materials.

YRM is the place to present your work in progress, come up with new ideas and learn about others’ work in a ​ friendly and open​ ​ atmosphere​. Master students, PhD students as well as young post-docs from all over Europe came together and discussed latest
advances in their fields. This year, talks at the YRM were 20 minutes, including 5 minutes of discussion. This gave everyone enough time to communicate his or her findings and receive feedback from other participants.

Read the full workshop report

2020-21 CECAM-Psi-k Research Conference

2020-21 CECAM-Psi-k  Research Conference
CECAM and Psi-k launch every year a call to organize a high-profile common research conference on an outstanding subject in the broad area of computational molecular and materials science; topics can range from applications in solid-state materials, soft matter, or biomolecules, to theoretical, methodological, and algorithmic advances. We particularly encourage proposals that promote interdisciplinary exchange across the areas indicated above and focus on exceptional scientific challenges that go beyond current boundaries and foster the discussion of new developments.

The conference should typically last between 3.5 and 5 days, and target a max of 100 participants, with a structure and format dedicated to foster plentiful discussions and informal interactions among the participants, proactively engaged by conference organizers and discussion leaders.

Proposals must be submitted online at  All conference proposals will be peer reviewed, discussed, and ranked by a scientific panel composed by 3 members proposed by CECAM, and by 3 trustees of Psi-k.

In the proposal, emphasis should be placed on outlining the challenging scientific issues, which will be the focus of the event, and in establishing the proposed list of speakers and participants. Active participation of scientists at different stages of their career, and especially early states, is very encouraged, as is diversity in the speakers and leaders.

The proposal should include information on the venue (anywhere in the EU, UK, and associated countries – Iceland, Norway, Albania, Bosnia and Herzegovina, North Macedonia, Montenegro, Serbia, Turkey, Israel, Moldova, Switzerland, Faroe Islands, Ukraine, Tunisia, Georgia, Armenia), and a tentative budget. Organizers can be based at institutions worldwide. CECAM and Psi-k are committed to support the event with up to 30,000 euro. Conference fees may be charged only to cover costs.

The call will be open until June 15th 2019 and the final outcome will be communicated at the end of July 2019. Proposals that are not selected will be considered also for regular CECAM and Psi-k activities, if the organizers activate this option in the submission. The conference must take place between Apr 2020 and Mar 2021, avoiding for this year overlaps with Psi-k 2020, that will be held in September 2020.

For further information, please do not hesitate to contact us.

Ignacio Pagonabarraga
CECAM Director
[email protected]
Nicola Marzari
Psi-k Chairman
[email protected]

5th TYC Energy Workshop: From Atoms to Applications

The Thomas Young Centre (TYC) held their 5th Energy workshop, entitled “From Atoms to Applications” from the 25th to the 27th of July 2018 at the Department of Chemistry in University College London. The meeting was focussed on the evolution of computational materials design, specifically for Energy Materials. The aim of the workshop was to showcase the latest advances in computational materials design and to promote discussion and debate on bridging theory and experiment. We had a range of excellent speakers on the side of theory and of experiment, and it was clear from the discussions after talks and at the coffee breaks and lunches that the combination of theory and experiment is alive and thriving. The programme featured invited talks from established leaders in the field and from emerging early career researchers in the area. We scheduled 15 minutes for questions after every presentation, and this prompted lively discussion and debate. We had 99 attendees ranging from established academics, to PDRAs, PhD students and even Undergraduate students, with representation by Senior Editors from Nature and Nature Materials. The workshop featured diverse energy applications such as oxide and proton conducting fuel cells, photocatalysis, photovoltaics, LEDs, catalysis, solid state batteries, organic electronics and amorphous oxides semiconductors.

Read the full report here.

Interface Properties in Organic & Hybrid Electronics (IPOE-2019)


2d International Conference on

Interface Properties in Organic and Hybrid Electronic:

Perspectives & Key Challenges

Cergy-Pontoise, France, 8-11 July 2019

IPOE-2019 will be entirely devoted to the physical phenomena occurring at organic/organic, organic/inorganic and organic/metallic interfaces

IPOE-2019 is a single-session conference, comprising a plenary lecture by Prof. Rudolph A. Marcus, Nobel Prize in Chemistry, 12 keynote- and invited lectures, 36 oral contributions, and a poster session. The conferences will be followed by ample time devoted to questions (20 min / 10 min / 5 min for KN / Invited / Oral Contributions respectively), in addition to discussions during a poster session. 

The conference will cover a broad range of areas related to both experimental and theoretical aspects of these processes, comprising the following topics (but not limited to):

  • Charge separation mechanisms
  • Charge generation mechanisms
  • Energy transfer processes
  • Energy landscape at interfaces
  • Materials for interface engineering
  • Interfacial versus bulk properties
  • Hybrid organic/inorganic interfaces
  • Metal/organic interfaces
  • Organic/organic interfaces
  • Solar energy conversion
  • Organic sensors and bioelectronics
  • Molecular spintronics
  • Organic and Hybrid SCs, O&H LEDs, OFETs
  • Experimental probes
  • Molecular modeling and theoretical models






Report: CECAM / PSI-K Workshop Bremen on Correlated electron physics beyond the Hubbard model

CECAM Report


Organizers: Tim O. Wehling (Bremen), Thomas Frauenheim (Bremen), Silke Biermann (Palaiseau Cedex), Johannes Lischner (London), Nikolay Prokofiev (Amherst, Massachusetts), Malte Schüler (Bremen), Andrew Millis (New York)

Venue: University of Bremen, Bremen Center for Computational Materials Science (BCCMS), Germany, 8th until 12th of October 2018

Sponsors: University of Bremen (BCCMS), Psi-k, DFG, CECAM

Electrons in real materials are subject to Coulomb interaction among each other. This interaction is long-ranged, gives rise to correlation effects, and often poses fundamental problems in ab initio simulations of real materials. A nowadays commonly used ab initio approach for strongly correlated materials is the augmentation of density functional (DFT) based methods with many-body treatments of the Hubbard model, such as the combination of DFT and dynamical mean field theory [1]. This approach, however, neglects all correlation effects stemming from non-local Coulomb interaction, since the Hubbard model only includes the on-site part of the interaction. Combining more sophisticated diagrammatic ab initio methods (GW) with methods and models which contain the long-range contributions of the interaction (EDMFT) [2] alleviates these problems in part but comes with the introduction of further approximations. Assessing the quality of such approaches is currently hampered by the fact that even the extended Hubbard model, which is the minimal many-body model capturing explicitly non-local interactions, is at best partially understood. Continue reading Report: CECAM / PSI-K Workshop Bremen on Correlated electron physics beyond the Hubbard model

Ab initio (from electronic structure) calculation of complex processes in materials