Organisers

• Paolo Umari (Università degli Studi di Padova, Italy)
• Davide Ceresoli (MIT, United Kingdom)
• David Prendergast (The Molecular Foundry, Lawrence Berkeley National Laboratory, USA)

Supports

   CECAM

Description

Please, visit the tutorial website:

http://sites.google.com/site/cecamspectra2010/

for the latest information and directions to Trieste.

In nanoscience the study and characterization of materials is possible thanks to the availability of a large set of experimental probes. However, a full understanding of these requires accurate modeling. With the use of state-of-the-art materials modeling codes, it is now possible to simulate from first-principles several experimental spectroscopies.

With this tutorial, we want to give the basis for the simulation of spectra in complex molecular and nanostructured systems using approaches based on density functional theory, including "beyond-DFT" methods such as time-dependent DFT and many-body perturbation theory, implemented on a pseudo-potential plane-waves basis framework.

We will focus on a comprehensive set of probes, such as:

- vibrational spectroscopies:neutron, infrared, Raman;
- spectroscopies involving core-electron excitations: x-ray absorption and x-ray photoemission;
- responses to magnetic fields: NMR and EPR spectroscopies;
- optical and electron  spectroscopies: direct and inverse photoemission and light absorption.

As the final goal of theoretical spectroscopy is the comparison with the corresponding experimental results, we will also provide a brief introduction from the experimental point of view. As the possibility of performing such calculations in large model structures has been due to the introduction of new algorithms, we will also focus on the recent advances in electronic structure techniques.

For the practical sessions, we will mainly use the packages of the Quantum-Espresso distribution.

We plan to cover the accomodation expenses of all the partecipants. Applications should be submitted before May 1st 2010. Decisions about acceptance will be communicated shortly thereafter.

References

-Light Scattering in Solids II, Springer, ed. M. Cardona
-P. T. Callaghan, Principles of Nuclear Magnetic Resonance Microscopy, Clarendon Press
-G. S. Rule and T. K. Hitchens, Fundamentals of Protein NMR Spectroscopy, Springer
-J. A. Weil and J. R. Bolton, Electron Paramagnetic Resonance, Wiley
-M. Knaupp, M. Buehl and V. G. Malkin, Calculation of NMR and EPR Parameters, Viley-VCH
-NEXAFS Spectroscopy, Joachim Stoehr, Springer Series in Surface Sciences 25, Springer (2nd Ed., 2003).
-"Electronic excitations: density-functional versus many-body Green function
approaches",
G. Onida, L. Reining and A. Rubio,
Rev. Mod. Phys. 74, 601 - 659 (2002)
-"Phonons and related crystal properties from density-functional perturbation
theory",
S. Baroni, S. de Gironcoli, A. Dal Corso, and P. Giannozzi
Rev. Mod. Phys. 73, 515 - 562 (2001)
-"Efficient Approach to Time-Dependent Density-Functional Perturbation Theory
for Optical Spectroscopy",
B. Walker, A.Marco Saitta, Ralph Gebauer, and Stefano Baroni,
Phys. Rev. Lett. 96, 113001 (2006)
-"Optimal representation of the polarization propagator for large-scale GW
calculations"
P. Umari, G. Stenuit, S. Baroni,
Phys. Rev. B 79, 201104 (R) (2009).
-" Medium-range structure of vitreous SiO2 obtained through first-principles
investigation of vibrational spectra",
L. Giacomazzi, P. Umari, A. Pasquarello,
Phys. Rev. B 79, 064202 (2009).