The Psi-k Community

Psi-k is a wide network of European researchers — working closely with many friends and colleagues around the world – that is intended to help build cooperation in the field of computational electronic structure calculations, in particular for crystalline quantum systems whose wave function Ψ has an associated wave vector k defining its periodicity, hence the name.  It is co-ordinated by a series of working groups from around Europe. It produces a monthly newsletter, organizes a major conference every five years, and allows researchers to email each other regarding job openings, events, and other topics of mutual interest. The network is also able to provide some degree of financial support for small workshops and schools, and for collaborative research visits.

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.

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.

Workshop on Spectroscopy and Dynamics of Photoinduced Electronic Excitations

From the 8th to the 12th May, over 100 scientists from over 30 countries have gathered at the Abdus Salam ICTP in Trieste, Italy, to attend the Workshop on Spectroscopy and Dynamics of Photoinduced Electronic Excitations. This workshop had the goal to put together experts in investigation of photoinduced electronic excitations in real materials. This field has experienced tremendous progress recently, mainly thanks to developments in experimental techniques, like ultrafast spectroscopy, and in theoretical methods, like many-body perturbation theory and time-dependent density functional theory. Processes of interest include photoabsorption, exciton dynamics, and charge transfer. These issues are of interest for fundamental research, but are also relevant for applications in photovoltaics, optoelectronics, and photocatalysis. The workshop consisted of lectures from leading experts in both theoretical and experimental research, and seminars on career development. Continue reading Workshop on Spectroscopy and Dynamics of Photoinduced Electronic Excitations

Share your forum posts and workshop reports to social media

Did you know that you can now share your Psi-k forum posts to Twitter and Facebook?

Reach a wider audience by tweeting your forum posts – or workshop reports – direct from the Psi-k website.

If you open the posts in the forums, or the workshop reports posted to the front page magazine, you will now see the sharing buttons at the bottom of the page.

Thank you to Mike Towler for his development work!

3rd NOMAD (Novel Materials Discovery) Industry Workshop

3rd NOMAD (Novel Materials Discovery) Industry Workshop
Cumberland Lodge, Windsor, Berkshire, SL4 2HP
February 5, 2018 to February 6, 2018

The objectives of NOMAD Centre of Excellence (CoE) include the creation of a materials encyclopaedia, the development of Big-Data analytics and advanced graphics tools for materials science and engineering. These goals are complementary with those of the other two CoEs supported by the European Commission and active in the field of CECAM activities (E-cam and Max). The NOMAD Researchers are currently creating a large, homogenized materials database, as well as the analytical tools and code developments necessary to extract information from it.

This was the third (and last) of a series of three industry meetings organised annually by NOMAD to get together with industry representatives. The purpose of the meeting is to listen and gather the feedback of industry on their needs and plans concerning materials data, and to in- form/train them on data-analytic tool-usage.  In addition, we share the recent developments NOMAD has carried out. At the end of each meeting, a commission made of NOMAD PI’s and selected Industrial representative discuss the outcome of the meeting and plan in which direction NOMAD development should go in order to meet the industry needs. In particular, the meeting is structured such that in a first instance, invited industry representatives present and discuss the main activities carried out in their company. In second instance, speakers from each NOMAD work package present the most recent developments and features incorporated into the NOMAD’s framework. Below we summarise what has been discussed for each work package.

Read the full workshop report here.

The electrode potential in electrochemistry – A challenge for electronic structure theory calculations

Castle Reisensburg near Ulm/Germany
November 26 – 29, 2017

Organizers: Axel Gro (Ulm University, Germany),
Michiel Sprik (Cambridge University, UK)

Processes at electrochemical electrode-electrolyte interfaces are of tremendous technological importance, in particular in the context of electrochemical energy storage and conversion. Still, atomistic  details of structures and processes at these interfaces are often still not known. This calls for a close collaboration between experiment and theory on an atomistic level. However, quantum chemical  studies addressing atomistic details of electrochemical interfaces face severe fundamental theoretical, computational and numerical

Among of the most severe problems is the proper theoretical quantum chemical description of the electrode potential. In electrochemistry, structures and properties at the  electrodeelectrolyte interface are governed by the electrode potential which has to be kept constant along the simulation of electrochemical processes. Yet, almost all of the fi rst-principles electronic structure studies addressing electrochemical systems are performed in the so called constant charge mode which, however, does not correspond to the set up used in electrochemistry experiments. It was the purpose of this purely theoretical workshop, organized by Axel Gro (Ulm University, Germany) and Michiel Sprik (Cambridge University, UK), to bring together experts in the fi eld of theoretical electrochemistry to review the current status of the field, but also to identify promising future developments. Although the main focus of the workshop was the proper theoretical  description of varying electrode potentials, also other issues such as the appropriate modeling of liquid electrolytes were addressed.

Read the full workshop report here.

Scientific report on the CECAM/Psi-K workshop “Electronic Structure Library coding workshop: ESL Demonstrator”

CECAM-HQ-EPFL, Lausanne, Switzerland, February 5-16, 2018

Organizers: Yann Pouillon (University of Cantabria, Spain), Micael Oliveira (Max Planck Institute for the Structure and Dynamics of Matter, Hamburg, Germany), Emilio Artacho (Cavendish Laboratory, University of Cambridge, United Kingdom), Volker Blum (Duke University, Durham, NC, USA), Mike Payne (University of Cambridge, United Kingdom), Fabiano Corsetti (Synopsys QuantumWise, Denmark)

Sponsors: CECAM and Psi-k


In 2014 the CECAM Electronic Structure Library (ESL) project was launched with the idea of fostering a new paradigm of library-based development for electronic structure. The aim of project is to create a common online repository of high-quality software libraries, programming interfaces and data standards in the field of electronic structure, which will facilitate reuse of code, interoperability between different code bases, rapid and efficient evolution to new computer architectures, and development of new methodologies.

The ESL aims to be a community-driven project which anyone can contribute to, with regular hands-on workshops being held to encourage developers to get involved in working on individual libraries and contributing to the ESL website, and to form collaborations between different code bases. The overarching strategy and direction of the ESL is also discussed and decided upon at these workshops, coordinated by a core group of organizers.

The main objective of this coding workshop was to write a simple DFT code from scratch using as many software libraries from the CECAM Electronic Structure Library as possible and without having to implement any complex numerical routines. Such demonstrator code will provide powerful, non-trivial examples of how the ESL libraries can be used by existing electronic structure codes. It will also provide a platform to test the performance and usability of the libraries in an environment as close as possible to real-life situations.

Continue reading Scientific report on the CECAM/Psi-K workshop “Electronic Structure Library coding workshop: ESL Demonstrator”

TSRC TDDFT Summer School and Excited States Workshop

The first US-based summer school and workshop on Time-Dependent Density Functional Theory (TDDFT) was held July 11-21, 2017 in Telluride, CO. TDDFT is increasingly used in
computational molecular and materials science to calculate electronic-excitation spectra and dynamics in a wide variety of applications, including photocatalysis, photo-controlled bond dissociation, and light-induced charge transfer. Software development in this community targets multiple software packages, many of which are open source, such as octopus, NWchem and [email protected], which are the ones our school focused on. The goal of this first iteration was to create a home for a national community of scholars, including users and developers, with a deep understanding of TDDFT, its capabilities, limitations, and high-performance computing context. We used this opportunity to explore interest in such an event in the future and based on overwhelmingly positive feedback from students and teachers, we intend to hold a similar school+workshop every two years in the US, in order to maintain the high level of interest that we witnessed and the enthusiasm amongst participants.

Read the full workshop report here.

Scientific report on the “Total Energy and Force Methods 2018” Workshop

Workshop logoTotal Energy and Force Methods 2018
Selwyn College, Cambridge, UK
9th – 11th January 2018

Organisers: Chris Pickard (University of Cambridge), Gábor Csányi (University of Cambridge), Mike Payne (University of Cambridge), Richard Needs (University of Cambridge), Michiel Sprik (University of Cambridge); External advisor: Mike Finnis (Imperial College London).

Funding: Psi-k, CCP9, the UKCP Consortium and the EPSRC CDT in Computational Methods for Materials Science.


This event was the latest in the “mini” series associated with the “Total Energy and Forces” workshops, held at ICTP in Trieste every two years. Since 1987 the Trieste workshops have taken place in odd-numbered years, alternating with the mini workshops, held each even-numbered year in a different location. The most recent workshops of the mini series took place in Madrid (2000), Tenerife (2002), Paris (2004), Cambridge (2006), Bonn (2008), Shanghai (2010), Barcelona (2012), Lausanne (2014) and Luxembourg (2016).

The workshop focused on the most recent developments in the field of electronic structure methods from the first-principles perspective, their diverse applications and mathematical foundations. The numerous approaches that are developed and used in the electronic-structure community provide the foundation for computing many physical and chemical properties of solids, liquids, and low-dimensional systems. However, there are numerous challenging applications for which the level of approximation is insufficient or where computational costs are prohibitive for accurate quantitative prediction of material properties. Therefore, continued efforts are devoted to an improvement of existing methods and the development of new methods.

Continue reading Scientific report on the “Total Energy and Force Methods 2018” Workshop

Anharmonicity and thermal properties of solids

10-12 January 2018, Paris, Institut Henri Poincaré

Conference organizers
Francois Bottin (CEA-DIF, France)
Johann Bouchet (CEA-DIF, France)
Matthieu Verstraete (University of Liege, Belgium)
Olle Hellman (California Institute of Technology (Caltech, US)

The quantitative prediction of harmonic phonon frequencies and thermodynamical quantities is one of the great successes of atomistic electronic structure in the past 30 years. Reality is however more complex, and vibrations are never purely harmonic. The systematic calculation of all possible anharmonic processes is a daunting task. Anharmonicity influences many important phenomena such as thermal expansion and Fourier’s law or coherent phonon generation. Heat transport is a central pillar of solid state physics and engineering, and influences many devices and properties. Both low and high conductivity materials have their uses, but historically its control has proved elusive. Simple mechanistic (grind it up) or back of the envelope (make it heavy) models reached their limits years ago. But only in the past 10-15 years a full chemically specific and atomistic prediction of lattice thermal properties has become possible. The field has blossomed at the crossroads of Chemistry, Physics, Engineerings (Energy, Mechanical, Electronic etc…), and benefi tted from a positive feedback loop
through re fined experiments and novel theories.

The aim of this workshop is to bring together cutting edge researchers in the numerical simulation and experimental determination of anharmonic phonon dynamics, and related properties (transport, ultrafast, electrons), to foster new approaches, new ideas, and give the field a decisive kick forward. We anticipate intense discussions and hotly contested debate about
where to go from here, as the terrain is wide open.

Read the full report here.

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