QESB 2009

Summer school on Materials modeling from first principles: theory and practice, ICMR, University of California at Santa Barbara, July 19-31, 2009

All the lectures’ slides, videos and exercises are available on the Materials Cloud web site

Program of the lectures

The school will cover basic concepts and recent advances and developments. The former include ground-state calculations for isolated molecules and extended systems, pseudopotential theory and plane-wave basis sets, forces, stresses, and geometry and reaction-path optimizations, linear-response theory and phonons, and ab-initio molecular dynamics. Advanced techniques will include first-principles vibrational (IR, Raman) and magnetic (EPR, NMR) spectroscopies, electron-phonon and phonon-phonon interactions, excited states (TDDFT and GW), DFT+U and non-collinear magnetism, Wannier functions and quantum transport.

FIRST WEEK

Sunday 19

Keynote lecture:

• • Prof. Walter Kohn (UCSB), Nearsightedness of Electronic Matter – Revisited

Monday 20: Ground state DFT, pseudopotentials, plane waves, kpoints, metals

Reminder of ground-state DFT, pseudopotentials, plane waves. Basis sets. The Hellman-Feynman theorem and beyond (Pulay). Coping with finite and infinite systems with plane waves: supercells and k-point sampling. Sampling occupied states in metals: smearing and tetrahedra. Self consistency. Molecular orbitals, Bloch states, orbital energies, energy bands.

Lectures:

• • Stefano Baroni, Electronic structure, density-functional theory, plane waves: a quick overview of terms and concepts;
  • Shobhana Narasimhan, DFT in practice: Some “Fundae”.

Labs:

• • Shobhana Narasimhan, Gabriele Sclauzero, Brandon Wood, Postprocessing and visualization. Energy bands and equation of state of Si, Al, or the like. A few simple molecular applications.

Keynote lecture

• • Prof. Steven Louie (UC Berkeley), First-Principles Studies and Physics of Carbon Nanostructures: Sheets, Tubes and Ribbons

Tuesday 21: Forces, stress; Atomic and cell optimizations; NEB

Hellman Feynman at work: atomic forces and crystal stress. Geometry optimization and BO molecular dynamics, algorithms (BFGS, Verlet, damped dynamics). Variable-cell optimization / dynamics. NEB.

Lectures:

• • Shobhana Narasimhan, Forces: Calculating Them and Using Them;
  • Stefano de Gironcoli, Stress, Enthalpy and Variable Cell Optimization;
  • Stefano de Gironcoli, Rare Events and Nudged Elastic Band.

Labs:

• • Nicola Bonini, Applications to clean/reconstructed surfaces, molecules, adsorbates, vacancies.

Keynote lecture:

• • Dr. Sadasivan Shankar (Intel), Top 10 Challenges for Enabling Computational (Virtual) Materials Design – A Nanotechnology Perspective

Wednesday 22: Second derivatives, response functions, DFPT

Density-functional perturbation theory: second derivatives of the energy and beyond, response functions. Phonon dispersions.

Lectures:

• • Stefano Baroni, Density-functional perturbation theory: forces, response functions, phonons, and all that;
  • Andrea Dal Corso, Introduction to density functional perturbation theory for lattice dynamics;
  • Andrea Dal Corso, Density functional perturbation theory II: phonon dispersions;

Labs:

• • Nicola Bonini Examples of phonon calculations with DFPT.

Keynote lecture:

• • Prof. Nicola Spaldin (UCSB), Using Density Functional Theory to Design New Materials

Thursday 23: LSDA, collinear and noncollinear magnetism; spin-orbit coupling; DFT+U

Spin magnetism, spin-polarized calculations, non collinear magnetism, spin-orbit coupling. DFT+U for strongly-correlated systems and transition-metal complexes.

Lectures:

• • Matteo Cococcioni, Magnetism and correlation in open-shell systems;
  • Andrea Dal Corso, Introduction to noncollinear magnetism and spin-orbit coupling in Quantum-ESPRESSO.

Labs:

• • Matteo Cococcioni, Examples of spin-polarized and DFT+U calculations, Andrea Dal Corso, Examples on Noncollinear magnetism and SO coupling.

Keynote lecture:

• • Prof. Richard Martin (UIUC), Electronic Structure from the top down: Starting from high temperature

Friday 24: Advanced DFPT and vibrational spectroscopies

Advanced (third-order) density-functional perturbation theory and vibrational spectroscopies (effective charges, Raman cross-sections, electron-phonon coupling and superconductivity)

Lectures:

• • Paolo Umari, First-principles vibrational spectroscopies;
  • Stefano de Gironcoli, electron-phonon interaction (slides) and phonon-phonon interaction.

Labs:

• • Paolo Umari (exercises), Stefano de Gironcoli (ex. el-ph) (ex. ph-ph)

Banquet in the evening

Saturday 25: Pseudopotential theory and applications

Introductory lecture and exercises on pseudopotential generation and testing using the atomic code ld1.x

Lectures:

• • Andrea Dal Corso, Pseudopotential generation and test by the ld1.x atomic code: an introduction;

Labs:

• • Andrea Dal Corso, Examples of pseudopotential generation and testing.

Second week

Monday 27: Excited states

Lectures:

• • Stefano Baroni, Density-functional perturbation theory goes time-dependent;
  • Paolo Umari, Photoemission spectroscopy: GW calculations for large systems.

Labs:

• • Dario Rocca, Paolo Umari, Liouville-Lanczos calculation of the TDDFT spectrum of simple molecules.

Free discussion

Tuesday 28: Classical MD, Ensembles, Ab-initio MD

Lectures:

• • Giulia Galli, classical MD, ensembles, ab-initio MD;
  • Francois Gygi, introduction to the Qbox code.

Labs:

• • Brandon Wood, Paolo Umari, Dario Rocca.

Wednesday 29: Car-Parrinello MD. Parallelization

Lectures:

• • Francois Gygi, Car-Parinello MD. Parallelization.

Labs:

• • Brandon Wood, Francois Gygi, Dario Rocca.

Poster session: in Loma Palona (8pm-10pm)

Thursday Jul 30: NMR and EPR spectroscopy

Lectures:

• • Ari Seitsonen, Introduction to NMR spectroscopy. Chemical shift, electric field gradients. How to analyze the results and compare to experiments. Implementation: GIPAW formalism and extension to solids;
  • Davide Ceresoli, Introduction to EPR spectroscopy. The spin hamiltonian. Calculation of EPR parameters: g-tensor and hyperfine couplings. Examples. Converse approach to NMR and EPR spectroscopy. How to run the code, generation of GIPAW pseudopotentials, how to analyze the output.

Labs:

• • Davide Ceresoli and Ari Seitsonen, Calculation of NMR spectra of heterocyclyc aromatic compounds. NMR for solids. Calculation of EPR spectra of small molecule radicals.

Keynote lecture:

• • Prof. Warren Pickett (UC Davis), Superconductivity & Strongly Correlated Electron Materials.

Friday 31: Wannier functions

Lectures:

• • Nicola Marzari, Fundamentals of Wannier functions (reciprocal space expressions for the spead, maximal localization, Wannier functions of a composite manifold of bands. The case of metals, and disengantlement of submanifolds to be localized);
  • Nicola Marzari, Wannier practice (Wannier functions and their relation with chemically intuitive concepts. Formal connection with the modern theory of polarization, and magnetization. Use of Wannier functions as accurate and efficient interpolators. Wannier functions as building blocks of large-scale Hamiltonians, and to construct Green’s functions and self-energy in the Landauer formalism).

Labs:

• • Nicolas Poilvert – Wannier functions for insulators. Metals and disentanglement. Model Hamiltonians. Wannier interpolation. Transport. files for the Lab.

Keynote lecture:

• • Prof. Matthias Scheffler (FHI/UCSB), The function of materials: multi-scale modeling from first principles.

BBQ in the evening