Electronic structure beyond density functional theory
1) Title, venue, organisers and purpose
- Title
Electronic structure beyond density functional theory
- Venue
Lorentz Center, Leiden, The Netherlands
For information on the facilities available at the Lorentz Center, see
http://www.lc.leidenuniv.nl/
- Dates
12-16 July 2004
- Organisers
Claudia Filippi
Universiteit Leiden
Instituut-Lorentz for Theoretical Physics
Leiden, The Netherlands
E-mail: 
Matthew Foulkes
Imperial College
Condensed Matter Theory Group, Blackett Laboratory
London, UK
E-mail: 
Shiwei Zhang
College of William and Mary
Department of Physics
Williamsburg, USA
E-mail: 
- Purpose
The proposed workshop serves multiple purposes:
* The workshop will be the launch meeting for the new quantum Monte Carlo working group WG2 of the ESF Ψk Programme.
* The workshop will bring together scientists from different communities (QMC, quantum chemistry, lattice models, DMFT, etc.) with a common interest in ab-initio many-body calculations, and will include focused discussions of several outstanding issues (ionic forces, transition metals, fermionic sign problem, etc.) We hope that the synergy brought by the mixture of participants will spawn new ideas and be fruitful for the growth of the field.
* The workshop will reach out to researchers doing quantum Monte Carlo in smaller or isolated groups, and to researchers who are not yet quantum Monte Carlo practitioners but who are interested in acquiring the expertise. The hands-on QMC tutorial proposed by Ceperley, Moroni and Baroni will introduce such people to the basic theory and the available computer programs; our workshop will then provide the necessary background and context, highlighting the state-of-the-art, the most challenging problems, and the topics of current interest.
2) Scientific content and motivation
An important area of research within electronic structure theory is the development of alternatives to density functional methods. In particular, it is vital for researchers in electronic structure theory to be able to access a hierarchy of techniques that can describe electronic correlations at higher and higher levels of precision. Quantum Monte Carlo methods are among the most successful of the post-DFT approaches, and yield accurate results for the correlated properties of large molecules and solids where conventional quantum chemistry methods are extremely difficult to apply. QMC is establishing itself as a unique tool for exploring electronic correlation in systems of interest to materials science and for obtaining conclusive answers in cases where DFT is shown to be inadequate.
As demonstrated by the incorporation of the new QMC working group WG2 into the Ψk Programme, the potential of QMC methods is now fully recognised within the electronic structure community,
Whilst keeping the focus of the workshop on quantum Monte Carlo, we intend to bring together researchers from several communities with a common interest in ab-initio many-body problems. Despite the potential of quantum Monte Carlo, the number of researchers in the field is still quite small and we feel that it is not only timely but also necessary to bring together QMC experts and new additions to the field, and to involve a larger community of practitioners in many-body calculations.
The QMC component of the workshop will focus on current methodological developments, including efforts to incorporate molecular dynamics and improve geometry optimisation schemes, to find more efficient ways of optimising trial wave functions, and to develop new algorithms alternative to the fixed-node diffusion Monte Carlo method. Speakers involved in pushing the frontier of applications to ever more complex systems will also be invited.
We are particularly interested in creating synergy with researchers from other fields, especially those who may be able to contribute new ideas to QMC. To this end, we plan to invite quantum chemists who have experience in techniques such as coupled cluster, which is now becoming competitive for certain large-scale applications, and who are interested in the generation of pseudopotentials for many-body problems. We also intend to invite experts on quantum Monte Carlo methods for lattice systems, since we believe that their expertise may aid the development of continuum methods. Finally, we will invite key speakers from the GW and DMFT communities, strengthening our links to the other two Ψk working groups on ab-initio many-body calculations.
3) Tentative list of speakers/discussion-leaders
We plan to have a combination of invited speakers and invited discussion leaders. The number of talks will be limited to 4-5 per day and ample time will be given to discussions which will play a key role and will focus on tackling several outstanding issues in quantum Monte Carlo.
Depending on the available funding, we may or may not be able to invite all the people listed below.
- Saverio Moroni Universita' di Roma La Sapienza, Italy
- Gaetano Senatore University of Trieste, Italy
- Sandro Sorella SISSA, Trieste, Italy
- Dario Bressanini Universita' dell'Insubria, Italy
- Stefano Baroni SISSA, Trieste, Italy
- Giovanni Bachelet Universita' di Roma La Sapienza, Italy
- Stephen Fahy University of Cork, Ireland
- Ben Wood Imperial College London, UK
- Richard Needs University of Cambridge, UK
- Rex Godby University of York, UK
- Lucia Reining Ecole Polytechnique, Palaiseau, France
- Michel Caffarel University of Paris (Jussieu), France
- Arne Luchow University of Dusseldorf, Germany
- Michael Dolg Univeristy of Bonn, Germany
- Martin Schutz University of Stuttgart, Germany
- Matthias Troyer ETH Zurich, Switzerland
- Ari Harju Helsinki University of Technology, Finland
- Alexander Lichtenstein University of Nijmegen, The Netherlands
- Steven White University of California, Irvine, USA
- Kevin Schmidt Arizona State University, USA
- Shiwei Zhang College of William and Mary, Williamsburg, USA
- Cyrus Umrigar Cornell University, USA
- Lubos Mitas North Carolina State University, USA
- David Ceperley University of Illinois, USA
- Jeffrey Grossman Lawrence Livermore National Laboratory, USA
- Richard Martin University of Illinois, USA
- Mal Kalos Lawrence Livermore National Laboratory, USA
- Andrew Rappe University of Pennsylvania, USA
4) Participants
We expect of the order of 45 participants, including the invited speakers, the invited discussion leaders and the 3 organisers. We are expecting of the order of 15 student/postdocs.
The main limitation on the number of participants will be financial. The CECAM workshop on "Diffusion Monte Carlo" organised in 2002 had 35 participants (a maximum set by CECAM) and additional applicants had to be turned down.
5) Outreach and tutorial element
We want to reach out to researchers doing quantum Monte Carlo in smaller groups as well as researchers who have just entered or are interested in entering the field. In this respect, our workshop will complement the hands-on tutorial proposed by Ceperley, Moroni and Baroni, introducing new participants to the research frontier.
To encourage the participation of younger researchers, we plan to allocate a substantial amount of the budget to pay their travel expenses in addition to lodging.
We also plan to involve researchers from the wider electronic structure community who can bring a different view of possible applications as well as new developments in methodology. An important aim is to foster links between the different communities (QMC, quantum chemistry, lattice models, GW, DMFT etc.) with a common interest in ab-initio many-body calculations.
The number of talks will be limited to 4-5 per day and ample time will be given to discussion, stimulating active participation from students and postdocs. We will also organise a poster session where young participants will be encouraged to present their work.
It is hoped that the meeting will help to create a stronger and broader quantum Monte Carlo community.
6) Budget
We would like to pay the lodging expenses of all participants. We expect that most European participants will pay their own travel expenses, but will encourage the participation of younger researchers by contributing to their travel costs where possible. We will also contribute to the travel expenses of the invited scientists from the USA.
Lodging 45 participants * 5 days * 70 euro = 15750 euro
Travel = 8000 euro
---------------------------------------------------------
Total = 23750 euro
The request for the ESF Ψk Programme is 9000 euro.
7) Additional funding
We are currently applying for funding from the Lorentz Center, which we hope will provide the remaining 14750 euro.
Prof. Zhang will apply for NSF funding to support the participation of US researchers.
8) Venue
We intend to held the workshop at the Lorentz Center, Leiden, The Netherlands.
The Center is devoted to the organisation of workshops, offering offices with internet access, a common room, a lecture room, and administrative help. The high quality of the venue will enable participants to interact closely, to work together on codes, and so on.
For more information on the Lorentz Center, see http://www.lc.leidenuniv.nl/
9) Funding for American participants
Prof. Zhang will apply for NSF funding to support the participation of US researchers.