Category Archives: Reports

School on Electron-Phonon Physics from First Principles

School on Electron-Phonon Physics from First Principles

19-23 March 2018, Miramare, Trieste, Italy

From 19th to 23rd March 2018 the first school entirely devoted to first-principles calculations of electron-phonon interactions was held at the Abdus Salam International Center for Theoretical Physics on the Miramare seafront in Trieste. This school welcomed 72 participants from 28 countries, and 14 staff members among lecturers, teaching assistants, and organizers. The event was sponsored jointly by the ICTP, the Psi-k organization, and the UK JC Maxwell Node of CECAM.

The purpose of this school was to offer training into ab initio calculations of many properties relating to the electron-phonon interaction, with a focus on  applications in condensed matter physics, materials physics, and nanoscience. As the accuracy, efficiency, and predictive power of ab initio computational methods keep improving steadily, calculations of electron-phonon interactions are becoming more accessible, and the number of groups moving into this field has been increasing rapidly during the last five years. Furthermore, as materials genomics and  high-throughput materials discovery expand towards ever more realistic calculations  of materials at finite temperature, it is expected that this field will continue  to grow and will eventually become a core component of materials design. In this broad context  it was felt that the time was ripe for introducing advanced training courses on  electron-phonon physics and the most recent ab initio approaches in this area. Continue reading School on Electron-Phonon Physics from First Principles

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

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
challenges.

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

Summary

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.

Introduction

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.

International Workshop on Ab initio Description of Iron and Steel: Mechanical Properties (ADIS2016)

The series of ADIS workshops is inspired by the impressive variety of competing mechanisms on the microscopic/atomic scale, which determine the performance of engineering materials such as steels. Accordingly, the main scope of the workshops is a thorough and detailed discussion of this behavior, in order to understand the underlying physics and to contribute to a further systematic improvement of the materials. We are convinced that a truly predictive approach to materials modeling needs to be based on a fundamental ab initio level, rooted in the laws of nature rather than empiricism. This is also the driving force for the collaborative research centre SFB761 Steel ab initio, which is devoted to a quantum-mechanically guided design in high- and medium-Mn steels and funding this workshop. We are grateful that the importance of this development is further recognized by the Psi-k Charity, which is financially supporting ADIS2016. Continue reading International Workshop on Ab initio Description of Iron and Steel: Mechanical Properties (ADIS2016)

scientific report on the Psi-k workshop “2D layered materials for opto-electronics: a theoretical/computational perspective”

 

   http://www.2dopt.eu/

                                       Rome, Italy, 18-19 December 2017

Organisers:

-Maurizia Palummo, Physics Department Tor Vergata University, Rome, Italy

-Giacomo Giorgi, Department of Civil & Environmental Engineering (DICA) University of Perugia, Italy

-Jeffrey Grossman, Materials Science Department MIT, Boston, USA

Funding:  Psi-K

Introduction

Isolating graphene for the first time in 2004, with its plethora of possible device⎯oriented appealing features, has paved the way towards the study of several new classes of layered two-dimensional (2D) materials.    In several opto-electronic applications such as those involving the solar-to energy conversion process, it is indeed extremely appealing to control the properties of well-understood 3D materials by reducing their dimensionality towards the 2D limit or, even better, to directly focus on naturally layered materials both free⎯standing and also coupled with other layered ones in order to boost the sunlight conversion efficiency. Moreover, stacked Van der Waals (vdW) heterostructures of 2D monolayers offer a unique playground to engineer the opto⎯electronic properties towards the realization of devices with different functionalities and with the availability of metallic, semiconducting, and insulating materials.  Due to their high surface to volume/ratio 2D⎯layered materials can harvest solar energy and generate electrons and holes, and they can also provide paths for the separation and diffusion of the photo-excited carriers. These are fundamental prerequisites for the realization of any photo⎯catalytic or photovoltaic cell.  The use of these emerging two-dimensional layered materials in technological applications presupposes a detailed knowledge of their chemical and physical properties. Theoretical methods and simulations play a fundamental role for the understanding and predicting these properties.  The goal of the workshop, collecting distinguished scientists in the field, has been to clarify the theoretical microscopic understanding of layered 2D Materials with a particular focus on applications in opto-electronics and solar⎯to⎯energy conversion.  An overview of the research at experimental level from experts in the field has also been given. Continue reading scientific report on the Psi-k workshop “2D layered materials for opto-electronics: a theoretical/computational perspective”