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.

3rd Daresbury QUESTAAL School

Daresbury Laboratory, UK, 13-17 May 2019

Organisers:

Daresbury: Leon Petit, Jerome Jackson, Martin Lüders

King’s College London: Mark van Schilfgaarde, Dimitar Pashov

The third Questaal school concentrated on qsGW and DMFT using the code’s new interface to the TRIQS library.  A series of tutorials enabled the 31 participants (mostly post-doctoral researchers and lecturers) to setup and run calculations starting from density functional theory and working up to GW, qsGW, LDA + Bethe Salpeter (BSE), or the inclusion of ladder diagrams in W: qsGW^BSE, and DMFT.  The participants were encouraged to experiment with a diverse range of materials, including itinerant magnets, f-electron systems, simple semiconductors and strongly correlated insulators.

In addition to the new TRIQS DMFT capability, the school also showcased recent developments in extending the GW self-energy by including phonon contributions and the first results of the new “Jigsaw Puzzle Orbital” basis, which is a full-potential analogue of the LMTO screening transformation which is short ranged and compact while still very precise. Continue reading 3rd Daresbury QUESTAAL School

Report on Workshop on Crystal Structure Prediction: Exploring the Mendeleev Table as a Palette to Design New Materials

Workshop on Crystal Structure Prediction: Exploring the Mendeleev Table as a Palette to Design New Materials

ICTP, Trieste, 14-18 January 2019

Final report

Thanks to enormous progress in computing power and in algorithm development, we are now closer to being able to predict the crystal structure of any material from the simple knowledge of its composition. This is the first necessary step for predicting in silico the property of a material, and planning modifications that could improve these properties. A critical discussion of the algorithms developed in the last years for the “in silico” prediction of crystal structures was the main theme of a workshop that took place at the Abdus Salam International Centre for Theoretical Physics (ICTP), in Trieste, Italy,  from 14 to 18 January 2019. The event, titled “Workshop on Crystal Structure Prediction: Exploring the Mendeleev Table as a Palette to Design New Materials”, focused in particular on approaches based on molecular modeling and was an opportunity to celebrate 2019 as the International Year of the Periodic Table, since crystal structure prediction is rooted in a deep knowledge of the properties of the atoms, and, in turn, numerous discoveries made with the help of crystal structure prediction, reveal new (often completely unexpected) sides of the behavior of the atoms. The Workshop was directed by the A. Laio, G. Desiraju, A. Oganov, and S. Scandolo. It was divided in two parts: the first three days were dedicated to an in-depth and critical discussion of the methods, with talks given by world experts in the field. The last two days were devoted to “hands-on” computer labs were the younger participants were given the opportunity to learn how to use the most advanced codes for crystal structure prediction, including the “Universal Structure Predictor: Evolutionary Xtallography” (USPEX) and the “Ab initio Random Structure Searching” (AIRSS). Continue reading Report on Workshop on Crystal Structure Prediction: Exploring the Mendeleev Table as a Palette to Design New Materials

Writing reproducible workflows for computational materials science

EPFL (Lausanne, Switzerland),  May 21-24, 2019

Today, many open questions in computational science call for more than individual computations using a single code. As the demand for integration and throughput increases, the skill of writing robust and reproducible workflows is becoming ever more important. In this context, the move towards open science raises the level of scrutiny and demands that workflows be recorded in a way that can be inspected and reused by scientific peers.

This hands-on tutorial introduced young researchers to writing reproducible computational workflows using the open-source AiiDA framework for workflow management and provenance tracking (http://​www.aiida.net), complemented by invited talks from experts in the field that highlight the power and the challenges involved with leveraging complex workflows in computational materials science.

Continue reading Writing reproducible workflows for computational materials science

ASCM2019

General comments

The Atomistic Simulation of Carbon and related Materials (ASCM2019) workshop (ascm2019.nanocarbon.fi) took place in Helsinki, Finland between the 10th and 12th of April 2019. The workshop venue was the historical main building of the University of Helsinki. The event was jointly organized by Flyura Djurabekova (University of Helsinki), Volker Deringer (University of Cambridge) and Miguel Caro (Aalto University).

A total of circa 45 participants (mostly from Europe but also from overseas) met at the heart of Helsinki for three days of discussion on the state of the art and future prospects of atomistic simulation of pure carbon compounds and nanostructures, functionalized carbon materials, carbon-containing molecules and silicon/SiC alloys. Focus topics with strong presence at the workshop were atomistic modeling of graphene and carbon nanotubes, amorphous carbon, molecular dynamics simulations of high-energy/irradiation effects, development and benchmarking of interatomic potentials and, prominently, machine learning applied to atomistic simulations in general and carbon science in particular. The oral sessions featured a nice combination of established and early-career researchers.

Continue reading ASCM2019

Psi-k 2020 Conference – First Announcement

As many of you know, every five years Psi-k organizes a general conference in its field; the next one will be held at EPFL in Lausanne, on Sep 14-17 2020. It’s the sixth in the series, after San Sebastian (2015), Berlin (2010) and Schwaebisch-Gmuend (2005, 2000, 1996). The last two events had more 1000+ participants each, making this the largest event worldwide in first-principles simulations, theory, and applications.

The conference will take place over 3.5 days, starting in the afternoon of Mon Sep 14, 2020, and will see 7 plenary speakers and more than 120 invited and 240 talks, organized around 42 symposia (and, of course, a MAD evening to shake it all off). All up-to-date information can be found at https://www.psik2020.net; registration will open in November 2019, so for the moment hold this date. Hotels listed are already ready to take bookings at the negotiated rates.

In conjunction with this announcement, we are also issuing a worldwide call to suggest thematic symposia for the conference – each symposium will last between 2 and 3 hours, and cover between 2 and 4 invited presentations (30 min each), and between 2 and 6 contributed presentations (15 min each), that will be chosen by the symposium organizers themselves among the abstracts submitted (deadline for all abstract submissions will be May 1, 2020).

In order to make a suggestion for a symposium, you need to have a group of up to 4 organizers, as broad and as diverse as possible, identify a symposium theme (keeping in mind that 16 symposia will be broadly dedicated to the core activities of the 16 Psi-k working groups, https://psi-k.net/groups/) and suggest between 2 to 4 invited speakers. Organizers of approved symposia will also be in charge, in May 2020, of selecting contributed talks (2 to 6) among all the abstracts submitted to the symposium by Psi-k 2020 participants.

The Psi-k 2020 Program Committee will evaluate in October 2019 all the submitted suggestions – the criteria will be

  1. scientific merit, timeliness, and interest of the topic
  2. intellectual diversity and inclusiveness of the speakers
  3. scientific merit of the organizers
  4. responding to the Psi-k mission statement (http://psi-k.net/)

You can find the symposium suggestion form at the bottom right of https://www.psik2020.net/program, or directly here: https://forms.gle/Q4QaVxPZgYuANQwWA

Deadline for suggestions is Sep 8 2019, midnight CEST (central european summer time).

Looking very much forward to a successful Psi-k 2020, and to seeing you all in Lausanne.

Nicola Marzari
Chair, Psi-k

Report on Green’s function methods: the next generation

Objectives:

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 (http://psi-k.net/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 (http://psi-k.net/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 http://psi-k.net/. 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 http://psi-k.net/workshops/ 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 https://www.dropbox.com/request/B79bboXnda0inodP0uoN.

Please name your file as follows:
Surname_Event_MonthYear.doc/pdf
(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

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