Real-space multiple-scattering theory of EXAFS and XANES

Size: px
Start display at page:

Download "Real-space multiple-scattering theory of EXAFS and XANES"

Transcription

1 Nordita School on Photon-Matter Interaction Stockholm, Sweden Oct 3-7, 2016 Real-space multiple-scattering theory of EXAFS and XANES J. J. Rehr, J. J. Kas and F. D. Vila

2 Outline Goals: -Real-space multiple-scattering (RSMS) Theory aka Real-space Green s function (RSGF) theory -Implementation of RSMS in FEFF Key approximations and limitations Effects of structure and disorder A few Advanced methods

3 Full spectrum XAS: Expt. Vs Theory fcc Al UV x-ray

4 The devil is in the details: edges, fine-structure fcc Al UV x-ray

5 Historical interpretation of EXAFS* *Stern Sayers Lytle, UW 1971 Short range order theory EXAFS EXAFS Fourier Transform Cu Shifted Radial Distribution shift X-ray Microscope! R nn BUT need to calibrate experiment with Standard

6 EXAFS Theory Quantitative theory of EXAFS: Theory behind FEFF6 & general summary J. J. Rehr & R.C. Albers Rev. Mod. Phys. 72, 621 (2000)

7 Advances in Theory FEFF9 Update of Rehr & Albers: Advanced techniques and ab initio treatment of many-body effects

8 RSGF in the hierarchy of spectroscopy methods sophistication Atomic models: e.g. de Groot. Atomic cross-sections, multiplet s theory with fitted parameters, crystal field model Hamiltonians DFT (Density Functional Theory): WIEN2k, ABINIT, VASP, CASTEP, StoBe, Orca, Accurate for ground-state properties, not reliable for excited states, Delta-SCF Final State Rule with core-hole Quasi-particle Green s Function Theory: FEFF9 Appropriate for excited states, NOT full potential BSE (Bethe-Salpeter Equation): Exc!ting, OCEAN, AI2NBSE. Accurate but demanding. Less user friendly. Misses excitations & satellites QC methods: MRCI, MRCC, CASPT2, QMC, etc, highly accurate but completely intractable

9 FEFF development philosophy Pretty good spectra Advantages: Real-space Fully relativistic, all-electron Semi-automated, user-friendly, easy to use Built for EXAFS and related x-ray spectroscopies Applicable to materials throughout the periodic table Disadvantages: Not always the best tool: Spherical potentials can lose accuracy near edges Quasi-particle theory only ignores multiplets, satellites

10 FEFF quantitative XANES theory in one diagram Inelastic Losses Self-energy Σ Real-Space Green s Function x-ray + Screened core-hole

11 Can you write an equation for the theory? P.A.M. Dirac

12 Answer: Exact EXAFS Equation* Effective Scattering Amplitude f eff S 0 2 Many body amplitude factor EXAFS measures local structure & disorder Mean free path λ k σ 2 Mean square vib amplitude Distance R Coordination N Disorder σ 2 *JJR, RC Albers, CR Natoli, EA Stern, Phys Rev B34, 4350 (1986)

13 BUT: need many parameters! Question: Can the EXAFS parameters k f eff Φ k σ 2 λ k S 0 2 be calculated theoretically?

14 FEFF: Many-body effective single particle Many-body Fermi s Golden Rule XAS absorption coefficient Effective Single particle Fermi s Golden Rule

15 FEFF: From sum-over-states to Green s function Effective Single particle Fermi s Golden Rule

16 FEFF: From sum-over-states to Green s function Effective Single particle Fermi s Golden Rule Density Matrix

17 FEFF: From sum-over-states to Green s function Effective Single particle Fermi s Golden Rule Density matrix from Green s function

18 FEFF: From sum-over-states to Green s function Effective Single particle Fermi s Golden Rule Substitute sum over final states with Green s function

19 FEFF: Local basis and matrix elements

20 What s a Green s function? Wave function in QM H Ψ = E Ψ Ψ(r) = Amplitude to find particle at r Green s function (H E) G = - δ(r-r ) G(r,r,E) = aka Propagator = Amplitude to go from r to r

21 FEFF: Local basis and matrix elements Insert complete set of states

22 FEFF: Local basis and matrix elements Insert complete set of states

23 FEFF: Local basis and matrix elements Insert complete set of states Matrix elements Green s Function matrix

24 Getting G: Multiple Scattering Theory Dyson s equation: Iterating:

25 Getting G: Multiple Scattering Dyson s equation: Iterating:

26 Getting G: Multiple Scattering Dyson s equation: Iterating: Atomic pot. partition

27 Getting G: Multiple Scattering Dyson s equation: Iterating: Atomic pot. partition Site scatt. matrix

28 Getting G: Multiple Scattering Dyson s equation: Iterating: Atomic pot. partition Site scatt. matrix

29 Getting G: Multiple Scattering

30 Getting G: Multiple Scattering Central atom contrib. EXAFS

31 Getting G: Multiple Scattering Central atom contrib. EXAFS Graphically: Path expansion

32 Getting G: Full Multiple Scattering

33 Getting G: Full Multiple Scattering Total scatt. matrix

34 Getting G: Full Multiple Scattering Total scatt. matrix Sum and invert XANES

35 Implementation: FEFF Code 89 atom cluster Core-hole, SCF potentials Essential! BN

36 Example: Pt EXAFS path expansion Phase Corrected EXAFS Fourier Transform * Rnn= fcc Pt χ(r) Path Expansion 15 paths No peak shift! R (Å) *Theoretical phases accurate distances to < 0.01 Å

37 Example: Pt XANES full multiple-scattering Pt L 3 -edge 1.4 Pt L 2 -edge (S. Bare, UOP) Normalized Absorption FEFF calculation Experiment' Normalized Absorption FEFF calculation Experiment PtL3_xmu '98feb002_xmu' PtL2_xmu '98feb004_xm 0.0 PtL3edge Photon Energy, ev PtL2edge Photon Energy, ev Good agreement: Relativistic FEFF8 code reproduces all spectral features, including absence of white line at L 2 -edge. Self-consistency essential: position of Fermi level strongly affects white line intensity

38 Green s Functions and Parallel Computation Energy E is just a parameter! 1/N CPU Natural parallelization Each CPU does one energy

39 Self-consistent Densities and Potentials Spectrum: Golden Rule

40 Key approximations in FEFF Dirac-Fock relativistic atomic states ; semi-relativistic scattering states Spherical overlapped muffin-tin potentials: Huge simplification of the problem Quasi-particle approximation: Electron propagates in lossy medium Approximate self-energy Core-hole treatment: RPA or DFT-Screened core-hole

41 The muffin-tin potential Scattering potential partition

42 The overlapped muffin-tin potential Better density: Resembles bonding Charge redistribution Overlap Region Nuclei Muffin-tin potential

43 FEFF Density of States

44 FEFF electron density

45 Disorder and Debye-Waller factors in XANES DW factors: Crucial for EXAFS Very little effect in XANES region Can be included anyway in single-scattering approx. Both ab initio and model forms Disorder: Can be crucial in XANES Need external input for FEFF simulations MD trajectories MC sampling

46 Quick intro to Ab Initio DW factors Multiple Scattering Path XAFS DW Factor Average commonly expressed in terms of the cumulant expansion FT of Ge EXAFS χ(k) Leading cumulants χ(r) 2 σ (1) R + σ R (Å) J. Kas et al. (2007)

47 EXAFS near-neighbor DW Factor of Cu CD (Correlated Debye): Standard FEFF LDA, hgga: Ab initio DW Isotropic bonding: Good CD results Expt: Fornasini et al. (2004)

48 EXAFS near-neighbor DW Factor of Ge CD (Correlated Debye): Default in FEFF LDA, hgga: Ab initio DW Directional bonding: Needs AIDW Expt: Dalba et al. (1999)

49 Ab Initio DW factors: Lanczos algorithm XAFS DW Factor for path R: VDOS expressed as imaginary part of the phonon propagator Seed state: Displacement along path Dynamical Matrix: Calculated using ab initio methods (abinit, Gaussian, VASP, etc)

50 Ab Initio DW Factors in Metal-Ligand Complexes Ru(bpy) 2 (AP)(H2O) ++ N(AP) Good agreement for tight ligands (bpy) Useful agreement for weak ligands (AP and H2O) Still within error margin N(bpy) Ru O R M-L (in Å) σ 2 (in 10-3 Å 2 ) Path Theory Exp Theory Exp Ru-N(bpy) ± ± Ru-N(AP) ± ±3 Ru-O ± ±7 Expt: Salassa et al., J. of Physics: Conference Series 190, (2009)

51 Beyond DFT: Quasi-particle Self-Energy Effects Quasi-particle (QP) effects: BN 89 atom cluster Ground state potential: Usually insufficient Need QP effects and SCF potentials

52 Improvements to the theory: key many body effects Treatment of the core hole: Screening DFT or RPA Chemical shifts Self-energy approximations: Need more than single-pole self-energy Many-body effects: Charge transfer excitations: Transition metal oxides, cuprates,

53 Core-hole issues: RPA Screened Core-hole Linear response: Comparison of the core-hole in H 2 O

54 Core-hole issues: Chemical shifts N in NH4 + and NO3 - : Extreme case of chemical shift (4.3 ev)

55 Self-energy : HL plasmon-pole model Based* on GW approx.: W W: Screened Coulomb interaction G Dielectric function: 1 st approximation: single plasmon pole *B.I. Lundqvist Phys. Kondens Materie, 6, pp. 206, (1967)

56 Self-energy model: many-pole model Based* on GW approx.: W W: Screened Coulomb interaction G Dielectric function: Key ingredient Usually external source FEFF OPCONS: Semi-quantitative approximation J. Kas et al., PRB 76, (2007)

57 Self-energy issues: Many-pole model Loss Function Cu Many-pole (full) better than Hedin-Lundqvist (dashed) vs even better theory (dot-dashed) Kas et al., PRB 76, (2007)

58 Other FEFF capabilities Quick overview of other FEFF capabilities: XES RIXS Compton Profiles Reciprocal space: impurity GF model Hubbard U method

59 Non-resonant X-ray Emission (XES) RDX (High explosive) Vila et al., J. Phys. Chem. A 2011, 115, 3243

60 Compton Profiles

61 Resonant Inelastic RIXS X-ray and Scattering COMPTON (RIXS) TiO 2 (Ti Kα) FEFF Expt.

62 Reciprocal space capability Faster/better for some crystals No supercell needed for core hole Use cif file for input: ** feff.inp CIF w-gan.cif KMESH 1000 CONTROL GaN: N K edge EELS, 001 orientation Still experimental Not fully tested K. Jorissen et al. Phys. Rev. B 81, (2010)

63 Strongly correlated systems: Hubbard GW+U U calculated using constrained RPA within RSMS Not yet fully tested (Nearly) parameter free MnO Phys. Rev. B (2012)

64 Other references:

65 Further information The FEFF Project website: URL: feffproject.org The FEFF Users Guide: URL: feffproject.org/feffproject-feff-documentation.html Developers contact: URL: feffproject.org/feffproject-contact.html

66 Summary Take away messages Know the basics of RSMS/RSGF theory Understand the key approximations in FEFF Know some of FEFF s advanced capabilities

67 The FEFF group: Seattle and beyond From left to right: Ken Nagle Yoshi Takimoto Kevin Jorissen Towfiq Ahmed Hadley Lawler Aleksi Soininen Fernando Vila Adam Sorini Alex Ankudinov Micah Prange John Vinson (Shauna Story) John Rehr Josh Kas (Egor Clevac)

Theory, Interpretation and Applications of X-ray Spectra*

Theory, Interpretation and Applications of X-ray Spectra* REU Seminar University of Washington 27 July, 2015 Theory, Interpretation and Applications of X-ray Spectra* J. J. Rehr et al. A theoretical horror story Starring Fernando Vila & Anatoly Frenkel with J.

More information

Theory and Parameter Free Calculations of EELS and X-ray Spectra

Theory and Parameter Free Calculations of EELS and X-ray Spectra M&M Conference Columbus, OH 24-28 June, 2016 Theory and Parameter Free Calculations of EELS and X-ray Spectra J.J. Rehr 1, J. J. Kas 1, K. Jorissen 2, and F. Vila 1 1 Department of Physics, University

More information

Theory and Interpretation of Core-level Spectroscopies*

Theory and Interpretation of Core-level Spectroscopies* Summer School: Electronic Structure Theory for Materials and Molecules IPAM Summer School, UCLA Los Angeles, CA 29 July, 2014 Theory and Interpretation of Core-level Spectroscopies* J. J. Rehr Department

More information

X-ray Spectroscopy Theory Lectures

X-ray Spectroscopy Theory Lectures TIMES Lecture Series SIMES-SLAC-Stanford Winter, 2017 X-ray Spectroscopy Theory Lectures J. J. Rehr I. Introduction to the Theory of X-ray spectra II. Real-space Green's function Theory and FEFF III. Inelastic

More information

Theory and Calculation of X-ray spectra. J. J. Kas

Theory and Calculation of X-ray spectra. J. J. Kas Theory and Calculation of X-ray spectra J. J. Kas Theoretical Spectroscopy Calculations GOAL: Next Generation Theory for Next Generation X-ray Sources TALK I Introduction II State-of-the-art III Next generation

More information

Core-level Spectroscopies with FEFF9 and OCEAN

Core-level Spectroscopies with FEFF9 and OCEAN Soleil Theory Day Synchrotron SOLEIL, Grand Amphi 6/5/2014 Core-level Spectroscopies with FEFF9 and OCEAN J. J. Rehr 1,4 K. Gilmore, 2,4 J. Kas, 1 J. Vinson, 3 E. Shirley 3 1 University of Washington,

More information

III. Inelastic losses and many-body effects in x-ray spectra

III. Inelastic losses and many-body effects in x-ray spectra TIMES Lecture Series SIMES-SLAC-Stanford March 2, 2017 III. Inelastic losses and many-body effects in x-ray spectra J. J. Rehr TALK: Inelastic losses and many-body effects in x-ray spectra Inelastic losses

More information

Inelastic losses and satellites in x-ray and electron spectra*

Inelastic losses and satellites in x-ray and electron spectra* HoW Exciting! Workshop 2016 August 3-11, 2016 Humboldt-Universität -Berlin Berlin, Germany Inelastic losses and satellites in x-ray and electron spectra* J. J. Rehr, J. J. Kas & L. Reining+ Department

More information

Calculations of X-ray Spectra in Real-space and Real-time

Calculations of X-ray Spectra in Real-space and Real-time X-Ray Science in the 21st Century Calculations of X-ray Spectra in Real-space and Real-time J. J. Rehr, F. Vila, Y. Takimoto Department of Physics University of Washington Seattle, WA USA Time (s) KITP,

More information

Cumulant Green s function approach for excited state and thermodynamic properties of cool to warm dense matter

Cumulant Green s function approach for excited state and thermodynamic properties of cool to warm dense matter HoW exciting! Workshop Humboldt University Berlin 7 August, 2018 Cumulant Green s function approach for excited state and thermodynamic properties of cool to warm dense matter J. J. Rehr & J. J. Kas University

More information

IV. Calculations of X-ray Spectra in Real-space and Real-time. J. J. Rehr

IV. Calculations of X-ray Spectra in Real-space and Real-time. J. J. Rehr TIMES Lecture Series SLAC-Stanford U March 2, 2017 IV. Calculations of X-ray Spectra in Real-space and Real-time J. J. Rehr Calculations of X-ray Spectra in Real-space and Real-time Goal: Real-space, real

More information

Core loss spectra (EELS, XAS)

Core loss spectra (EELS, XAS) Core loss spectra (EELS, XAS) Kevin Jorissen University of Washington (USA) WIENk 013 Penn State 1. Concepts WIENk calculates ELNES / XANES EELS : Electron Energy Loss Spectroscopy XAS: X-ray Absorption

More information

HANDS- ON TUTORIAL: FINITE DIFFERENCE METHOD CALCULATIONS FOR NEAR- EDGE AND EXTENDED RANGE X- RAY ABSORPTION FINE STRUCTURE

HANDS- ON TUTORIAL: FINITE DIFFERENCE METHOD CALCULATIONS FOR NEAR- EDGE AND EXTENDED RANGE X- RAY ABSORPTION FINE STRUCTURE HANDS- ON TUTORIAL: FINITE DIFFERENCE METHOD CALCULATIONS FOR NEAR- EDGE AND EXTENDED RANGE X- RAY ABSORPTION FINE STRUCTURE Jay D. Bourke Postdoctoral Fellow in X-ray Science! School of Physics,! University

More information

Introduction of X-ray Absorption Near Edge Structure (XANES)

Introduction of X-ray Absorption Near Edge Structure (XANES) Introduction of X-ray Absorption Near Edge Structure (XANES) 2012 년 2 월 29 일 11:00 11:50 Eun Suk Jeong February 29-March 1, 2012 xafs school Outline 1. Introduction of XANES 2. Structural and chemical

More information

Part 1: What is XAFS? What does it tell us? The EXAFS equation. Part 2: Basic steps in the analysis Quick overview of typical analysis

Part 1: What is XAFS? What does it tell us? The EXAFS equation. Part 2: Basic steps in the analysis Quick overview of typical analysis Introduction to XAFS Part 1: What is XAFS? What does it tell us? The EXAFS equation Part 2: Basic steps in the analysis Quick overview of typical analysis Tomorrow Measurement methods and examples The

More information

Exploring the anomalous behavior of metal nanocatalysts with finite temperature AIMD and x-ray spectra

Exploring the anomalous behavior of metal nanocatalysts with finite temperature AIMD and x-ray spectra Exploring the anomalous behavior of metal nanocatalysts with finite temperature AIMD and x-ray spectra F.D. Vila DOE grant DE-FG02-03ER15476 With computer support from DOE - NERSC. Importance of Theoretical

More information

X-ray absorption spectroscopy.

X-ray absorption spectroscopy. X-ray absorption spectroscopy www.anorg.chem.uu.nl/people/staff/frankdegroot/ X-ray absorption spectroscopy www.anorg.chem.uu.nl/people/staff/frankdegroot/ Frank de Groot PhD: solid state chemistry U Nijmegen

More information

Chapter 2 Theory and Analysis of XAFS

Chapter 2 Theory and Analysis of XAFS Chapter 2 Theory and Analysis of XAFS John J. Rehr, Joshua J. Kas, Fernando D. Vila, and Matthew Newville 2.1 Theory of EXAFS 2.1.1 Introduction Owing to its element specific and short-range nature, core-level

More information

Core-Level spectroscopy. Experiments and first-principles calculations. Tomoyuki Yamamoto. Waseda University, Japan

Core-Level spectroscopy. Experiments and first-principles calculations. Tomoyuki Yamamoto. Waseda University, Japan Core-Level spectroscopy Experiments and first-principles calculations Tomoyuki Yamamoto Waseda University, Japan 22 nd WIEN2k workshop Jun. 26 th, 2015@Singapore Outline What is core-level spectroscopy

More information

Introduction to EXAFS data analysis. Shelly D. Kelly Argonne National Laboratory

Introduction to EXAFS data analysis. Shelly D. Kelly Argonne National Laboratory Introduction to EXAFS data analysis Shelly D. Kelly Argonne National Laboratory Data processing overview Absorption data Crystal structures (Atoms) Background subtracted EXAFS data (IFEFFIT) Theoretical

More information

An Introduction to XAFS

An Introduction to XAFS An Introduction to XAFS Matthew Newville Center for Advanced Radiation Sources The University of Chicago 21-July-2018 Slides for this talk: https://tinyurl.com/larch2018 https://millenia.cars.aps.anl.gov/gsecars/data/larch/2018workshop

More information

Electron energy loss spectroscopy (EELS)

Electron energy loss spectroscopy (EELS) Electron energy loss spectroscopy (EELS) Phil Hasnip Condensed Matter Dynamics Group Department of Physics, University of York, U.K. http://www-users.york.ac.uk/~pjh503 Many slides courtesy of Jonathan

More information

Today s Outline - April 07, C. Segre (IIT) PHYS Spring 2015 April 07, / 30

Today s Outline - April 07, C. Segre (IIT) PHYS Spring 2015 April 07, / 30 Today s Outline - April 07, 2015 C. Segre (IIT) PHYS 570 - Spring 2015 April 07, 2015 1 / 30 Today s Outline - April 07, 2015 PHYS 570 days at 10-ID C. Segre (IIT) PHYS 570 - Spring 2015 April 07, 2015

More information

Optical Absorption of N-Doped Diamond

Optical Absorption of N-Doped Diamond Optical Absorption of N-Doped Diamond Winnie Hui Yi Liang, Fernando Vila, Joshua Kas, Francois Farges, and John J. Rehr Department of Physics, University of Washington, Seattle, WA 989 Laboratoire de minralogie

More information

Molecular dynamics simulations of EXAFS in germanium

Molecular dynamics simulations of EXAFS in germanium Cent. Eur. J. Phys. 93 2011 710-715 DOI: 10.2478/s11534-010-0074-0 Central European Journal of Physics Molecular dynamics simulations of EXAFS in germanium Research Article Janis Timoshenko Alexei Kuzmin

More information

Optical Properties of Solid from DFT

Optical Properties of Solid from DFT Optical Properties of Solid from DFT 1 Prof.P. Ravindran, Department of Physics, Central University of Tamil Nadu, India & Center for Materials Science and Nanotechnology, University of Oslo, Norway http://folk.uio.no/ravi/cmt15

More information

Name: (a) What core levels are responsible for the three photoelectron peaks in Fig. 1?

Name: (a) What core levels are responsible for the three photoelectron peaks in Fig. 1? Physics 243A--Surface Physics of Materials: Spectroscopy Final Examination December 16, 2014 (3 problems, 100 points total, open book, open notes and handouts) Name: [1] (50 points), including Figures

More information

X-ray Spectroscopy. Interaction of X-rays with matter XANES and EXAFS XANES analysis Pre-edge analysis EXAFS analysis

X-ray Spectroscopy. Interaction of X-rays with matter XANES and EXAFS XANES analysis Pre-edge analysis EXAFS analysis X-ray Spectroscopy Interaction of X-rays with matter XANES and EXAFS XANES analysis Pre-edge analysis EXAFS analysis Element specific Sensitive to low concentrations (0.01-0.1 %) Why XAS? Applicable under

More information

Basics of EXAFS Data Analysis

Basics of EXAFS Data Analysis Basics of EXAFS Data Analysis Shelly Kelly EXAFS Analysis 2009 UOP LLC. All rights reserved. Data processing overview Introduction to Artemis Modeling Cu foil Background subtraction using theory Modeling

More information

EXAFS. Extended X-ray Absorption Fine Structure

EXAFS. Extended X-ray Absorption Fine Structure AOFSRR Cheiron School 2010, SPring-8 EXAFS Oct. 14th, 2010 Extended X-ray Absorption Fine Structure Iwao Watanabe Ritsumeikan University EXAFS Theory Quantum Mechanics Models Approximations Experiment

More information

Interpreting XANES. Grant Bunker Professor of Physics BCPS/CSRRI Illinois Institute of Technology Chicago, Illinois

Interpreting XANES. Grant Bunker Professor of Physics BCPS/CSRRI Illinois Institute of Technology Chicago, Illinois Interpreting XANES Grant Bunker Professor of Physics BCPS/CSRRI Illinois Institute of Technology Chicago, Illinois bunker@iit.edu Scope of this talk The literature abounds with empirical correlations between

More information

Optical Properties of Semiconductors. Prof.P. Ravindran, Department of Physics, Central University of Tamil Nadu, India

Optical Properties of Semiconductors. Prof.P. Ravindran, Department of Physics, Central University of Tamil Nadu, India Optical Properties of Semiconductors 1 Prof.P. Ravindran, Department of Physics, Central University of Tamil Nadu, India http://folk.uio.no/ravi/semi2013 Light Matter Interaction Response to external electric

More information

arxiv: v1 [cond-mat.mtrl-sci] 30 Sep 2010

arxiv: v1 [cond-mat.mtrl-sci] 30 Sep 2010 Bethe-Salpeter Equation Calculations of Core Excitation Spectra J. Vinson, J. J. Rehr, and J. J. Kas Dept. of Physics, Univ. of Washington, Seattle, WA 98195 E. L. Shirley arxiv:1010.0025v1 [cond-mat.mtrl-sci]

More information

3. EXAFS Data Analysis using Athena 2012 년 2 월 29 일 13:30 14:20

3. EXAFS Data Analysis using Athena 2012 년 2 월 29 일 13:30 14:20 3. EXAFS Data Analysis using Athena 2012 년 2 월 29 일 13:30 14:20 IFEFFIT package FEFFIT Fit χ(k) data to the theoretical calculations of FEFF, and assess the errors in the fitting parameters. The fitting

More information

Simulating Spectra. Travis Jones 19 Jan 2018

Simulating Spectra. Travis Jones 19 Jan 2018 Simulating Spectra Travis Jones 19 Jan 2018 Introduction Why should you care about calculating spectra? What kinds of spectra can you compute? What types of approaches are there? What are the pitfalls?

More information

Photon Interaction. Spectroscopy

Photon Interaction. Spectroscopy Photon Interaction Incident photon interacts with electrons Core and Valence Cross Sections Photon is Adsorbed Elastic Scattered Inelastic Scattered Electron is Emitted Excitated Dexcitated Stöhr, NEXAPS

More information

Introduction to X-ray Absorption Spectroscopy, Extended X-ray Absorption Fine Structure

Introduction to X-ray Absorption Spectroscopy, Extended X-ray Absorption Fine Structure Mini-school X-ray Absorption Spectroscopy Introduction to X-ray Absorption Spectroscopy, Extended X-ray Absorption Fine Structure Martin C. Feiters, IMM, HG 03.021, Radboud University Heijendaalsweg 153,

More information

X-ray Absorption Spectroscopy

X-ray Absorption Spectroscopy X-ray Absorption Spectroscopy Matthew Newville Center for Advanced Radiation Sources University of Chicago 12-Sept-2014 SES VI SES VI 12-Sept-2014 SES VI What Is XAFS? X-ray Absorption Fine-Structure (XAFS)

More information

Probing Matter: Diffraction, Spectroscopy and Photoemission

Probing Matter: Diffraction, Spectroscopy and Photoemission Probing Matter: Diffraction, Spectroscopy and Photoemission Anders Nilsson Stanford Synchrotron Radiation Laboratory Why X-rays? VUV? What can we hope to learn? 1 Photon Interaction Incident photon interacts

More information

André Schleife Department of Materials Science and Engineering

André Schleife Department of Materials Science and Engineering André Schleife Department of Materials Science and Engineering Yesterday you (should have) learned this: http://upload.wikimedia.org/wikipedia/commons/e/ea/ Simple_Harmonic_Motion_Orbit.gif 1. deterministic

More information

GW quasiparticle energies

GW quasiparticle energies Chapter 4 GW quasiparticle energies Density functional theory provides a good description of ground state properties by mapping the problem of interacting electrons onto a KS system of independent particles

More information

Faddeev Random Phase Approximation (FRPA) Application to Molecules

Faddeev Random Phase Approximation (FRPA) Application to Molecules Faddeev Random Phase Approximation (FRPA) Application to Molecules Matthias Degroote Center for Molecular Modeling (CMM) Ghent University INT 2011 Spring Program Fermions from Cold Atoms to Neutron Stars:

More information

FEFF8. The FEFF Project Department of Physics University of Washington

FEFF8. The FEFF Project Department of Physics University of Washington FEFF8 The FEFF Project Department of Physics University of Washington User s Guide, feff v8.40 updated August 21, 2006 Abstract feff is ab initio self-consistent real space multiple-scattering code for

More information

Basics of EXAFS data analysis. Shelly Kelly Argonne National Laboratory, Argonne, IL

Basics of EXAFS data analysis. Shelly Kelly Argonne National Laboratory, Argonne, IL Basics of EXAFS data analysis Shelly Kelly Argonne National Laboratory, Argonne, IL X-ray-Absorption Fine Structure APS monochromator slits Sample I 0 I t Ion Chambers I f Attenuation of x-rays I t = I

More information

Practical Guide to Density Functional Theory (DFT)

Practical Guide to Density Functional Theory (DFT) Practical Guide to Density Functional Theory (DFT) Brad Malone, Sadas Shankar Quick recap of where we left off last time BD Malone, S Shankar Therefore there is a direct one-to-one correspondence between

More information

Muffin-tin potentials in EXAFS analysis

Muffin-tin potentials in EXAFS analysis J. Synchrotron Rad. (5)., doi:.7/s6577555 Supporting information Volume (5) Supporting information for article: Muffin-tin potentials in EXAFS analysis B. Ravel Supplemental materials: Muffin tin potentials

More information

Basics of EXAFS Processing

Basics of EXAFS Processing Basics of EXAFS Processing Shelly Kelly 2009 UOP LLC. All rights reserved. X-ray-Absorption Fine Structure Attenuation of x-rays It= I0e-µ(E) x Absorption coefficient µ(e) If/I0 2 File Number X-ray-Absorption

More information

Practical approach to EXAFS Data Analysis

Practical approach to EXAFS Data Analysis Practical approach to EXAFS Data Analysis by Alexei Kuzmin Institute of Solid State Physics, University of Latvia Kengaraga street 8, LV-1063 Riga, Latvia E-mail: a.kuzmin@cfi.lu.lv Software for EXAFS

More information

Part II. Fundamentals of X-ray Absorption Fine Structure: data analysis

Part II. Fundamentals of X-ray Absorption Fine Structure: data analysis Part II Fundamentals of X-ray Absorption Fine Structure: data analysis Sakura Pascarelli European Synchrotron Radiation Facility, Grenoble, France Page 1 S. Pascarelli HERCULES 2016 Data Analysis: EXAFS

More information

Spettroscopia risonante di stati elettronici: un approccio impossibile senza i sincrotroni

Spettroscopia risonante di stati elettronici: un approccio impossibile senza i sincrotroni Spettroscopia risonante di stati elettronici: un approccio impossibile senza i sincrotroni XAS, XMCD, XES, RIXS, ResXPS: introduzione alle spettroscopie risonanti * Dipartimento di Fisica - Politecnico

More information

Doped lithium niobate

Doped lithium niobate Chapter 6 Doped lithium niobate Figure 6.1: a) An iron-doped LiNbO 3 crystal has been illuminated for days with a light stripe. As a result, a region with deficit of Fe 2+ (more Fe 3+ ) and saturated with

More information

arxiv: v2 [cond-mat.str-el] 7 Mar 2012

arxiv: v2 [cond-mat.str-el] 7 Mar 2012 Multiplet ligand-field theory using Wannier orbitals. arxiv:1111.4940v2 [cond-mat.str-el] 7 Mar 2012 M. W. Haverkort, 1 M. Zwierzycki, 2 and O. K. Andersen 1 1 Max Planck Institute for Solid State Research,

More information

Many body physics issues with the core-hole propagator and resonant inelastic X-ray scattering

Many body physics issues with the core-hole propagator and resonant inelastic X-ray scattering Many body physics issues with the core-hole propagator and resonant inelastic X-ray scattering Jim Freericks (Georgetown University) Funding: Civilian Research and Development Foundation In collaboration

More information

Applications of core-level spectroscopy

Applications of core-level spectroscopy Applications of core-level spectroscopy Rebecca Nicholls Outline of talk!! Bonding information!! EXELFS!! Core hole!! Magnetism, dichroism, temperature!! Multiplet calculations Combining experiment and

More information

DMDW: A set of tools to calculate Debye-Waller factors and other related quantities using dynamical matrices.

DMDW: A set of tools to calculate Debye-Waller factors and other related quantities using dynamical matrices. DMDW: A set of tools to calculate Debye-Waller factors and other related quantities using dynamical matrices. DMDW is a set of tools developed to calculate Debye-Waller (DW) factors and other related quantities

More information

Simo Huotari University of Helsinki, Finland TDDFT school, Benasque, Spain, January 2012

Simo Huotari University of Helsinki, Finland TDDFT school, Benasque, Spain, January 2012 Overview of spectroscopies III Simo Huotari University of Helsinki, Finland TDDFT school, Benasque, Spain, January 2012 Motivation: why we need theory Spectroscopy (electron dynamics) Theory of electronic

More information

Neutral Electronic Excitations:

Neutral Electronic Excitations: Neutral Electronic Excitations: a Many-body approach to the optical absorption spectra Claudio Attaccalite http://abineel.grenoble.cnrs.fr/ Second Les Houches school in computational physics: ab-initio

More information

Core Level Spectroscopies

Core Level Spectroscopies Core Level Spectroscopies Spectroscopies involving core levels are element-sensitive, and that makes them very useful for understanding chemical bonding, as well as for the study of complex materials.

More information

General introduction to XAS

General introduction to XAS General introduction to XAS Júlio Criginski Cezar LNLS - Laboratório Nacional de Luz Síncrotron CNPEM - Centro Nacional de Pesquisa em Energia e Materiais julio.cezar@lnls.br 5 th School on X-ray Spectroscopy

More information

Theoretical spectroscopy beyond quasiparticles

Theoretical spectroscopy beyond quasiparticles A direct approach to the calculation of many-body Green s functions: Theoretical spectroscopy beyond quasiparticles Lucia Reining Palaiseau Theoretical Spectroscopy Group Palaiseau Theoretical Spectroscopy

More information

Key concepts in Density Functional Theory (II) Silvana Botti

Key concepts in Density Functional Theory (II) Silvana Botti Kohn-Sham scheme, band structure and optical spectra European Theoretical Spectroscopy Facility (ETSF) CNRS - Laboratoire des Solides Irradiés Ecole Polytechnique, Palaiseau - France Temporary Address:

More information

Linear-response excitations. Silvana Botti

Linear-response excitations. Silvana Botti from finite to extended systems 1 LSI, CNRS-CEA-École Polytechnique, Palaiseau, France 2 LPMCN, CNRS-Université Lyon 1, France 3 European Theoretical Spectroscopy Facility September 3, 2008 Benasque, TDDFT

More information

Comparative XAFS studies of some Cobalt complexes of (3-N- phenyl -thiourea-pentanone-2)

Comparative XAFS studies of some Cobalt complexes of (3-N- phenyl -thiourea-pentanone-2) Journal of Physics: Conference Series PAPER OPEN ACCESS Comparative XAFS studies of some Cobalt complexes of (3-N- phenyl -thiourea-pentanone-2) To cite this article: Namrata soni et al 2016 J. Phys.:

More information

A Green Function Method for Large Scale Electronic Structure Calculations. Rudolf Zeller

A Green Function Method for Large Scale Electronic Structure Calculations. Rudolf Zeller A Green Function Method for Large Scale Electronic Structure Calculations Rudolf Zeller Institute for Advanced Simulation, Forschungszentrum Jülich Electronic structure calculations (density functional

More information

X-ray Absorption Spectroscopy Eric Peterson 9/2/2010

X-ray Absorption Spectroscopy Eric Peterson 9/2/2010 X-ray Absorption Spectroscopy Eric Peterson 9/2/2010 Outline Generation/Absorption of X-rays History Synchrotron Light Sources Data reduction/analysis Examples Crystallite size from Coordination Number

More information

The 2p X-ray absorption spectra of transition metal systems: New developments and ab-initio routes.

The 2p X-ray absorption spectra of transition metal systems: New developments and ab-initio routes. The 2p X-ray absorption spectra of transition metal systems: New developments and ab-initio routes. Frank de Groot Department of Chemistry, Utrecht University, Netherlands f.m.f.degroot@uu.nl Introduction

More information

Many electrons: Density functional theory Part II. Bedřich Velický VI.

Many electrons: Density functional theory Part II. Bedřich Velický VI. Many electrons: Density functional theory Part II. Bedřich Velický velicky@karlov.mff.cuni.cz VI. NEVF 514 Surface Physics Winter Term 013-014 Troja 1 st November 013 This class is the second devoted to

More information

Spatially resolving density-dependent screening around a single charged atom in graphene

Spatially resolving density-dependent screening around a single charged atom in graphene Supplementary Information for Spatially resolving density-dependent screening around a single charged atom in graphene Dillon Wong, Fabiano Corsetti, Yang Wang, Victor W. Brar, Hsin-Zon Tsai, Qiong Wu,

More information

A Practical Introduction to Multiple Scattering Theory

A Practical Introduction to Multiple Scattering Theory A Practical Introduction to Multiple Scattering Theory Bruce Ravel ravel@phys.washington.edu http://feff.phys.washington.edu/~ravel/ Version 0.1 July 19, 2005 Abstract In recent years, the ability to interpret

More information

Resonant Inelastic X-ray Scattering on elementary excitations

Resonant Inelastic X-ray Scattering on elementary excitations Resonant Inelastic X-ray Scattering on elementary excitations Jeroen van den Brink Ament, van Veenendaal, Devereaux, Hill & JvdB Rev. Mod. Phys. 83, 705 (2011) Autumn School in Correlated Electrons Jülich

More information

Elastic and Inelastic Scattering in Electron Diffraction and Imaging

Elastic and Inelastic Scattering in Electron Diffraction and Imaging Elastic and Inelastic Scattering in Electron Diffraction and Imaging Contents Introduction Symbols and definitions Part A Diffraction and imaging of elastically scattered electrons Chapter 1. Basic kinematical

More information

Introduction to XAFS. Grant Bunker Associate Professor, Physics Illinois Institute of Technology. Revised 4/11/97

Introduction to XAFS. Grant Bunker Associate Professor, Physics Illinois Institute of Technology. Revised 4/11/97 Introduction to XAFS Grant Bunker Associate Professor, Physics Illinois Institute of Technology Revised 4/11/97 2 tutorial.nb Outline Overview of Tutorial 1: Overview of XAFS 2: Basic Experimental design

More information

Improved Electronic Structure and Optical Properties of sp-hybridized Semiconductors Using LDA+U SIC

Improved Electronic Structure and Optical Properties of sp-hybridized Semiconductors Using LDA+U SIC 286 Brazilian Journal of Physics, vol. 36, no. 2A, June, 2006 Improved Electronic Structure and Optical Properties of sp-hybridized Semiconductors Using LDA+U SIC Clas Persson and Susanne Mirbt Department

More information

The Gutzwiller Density Functional Theory

The Gutzwiller Density Functional Theory The Gutzwiller Density Functional Theory Jörg Bünemann, BTU Cottbus I) Introduction 1. Model for an H 2 -molecule 2. Transition metals and their compounds II) Gutzwiller variational theory 1. Gutzwiller

More information

The two-body Green s function

The two-body Green s function The two-body Green s function G ( x, x, x, x ) T 1 3 4 ( x ) ( x ) ( x ) ( x ) 1 3 4 (Heisenberg picture operators, average over interacting g.s.) Relevant to ground state energy and magnetism, screened

More information

X-Ray Emission Spectroscopy

X-Ray Emission Spectroscopy X-Ray Emission Spectroscopy Axel Knop-Gericke knop@fhi-berlin.mpg.de Core Level Spectroscopy Anders Nilsson. Journal of Electron Spectroscopy and Related Phenomena 126 (2002) 3-42 Creation of core holes

More information

Structural characterization. Part 2

Structural characterization. Part 2 Structural characterization Part Determining partial pair distribution functions X-ray absorption spectroscopy (XAS). Atoms of different elements have absorption edges at different energies. Structure

More information

Progress & challenges with Luttinger-Ward approaches for going beyond DFT

Progress & challenges with Luttinger-Ward approaches for going beyond DFT Progress & challenges with Luttinger-Ward approaches for going beyond DFT Sohrab Ismail-Beigi Yale University Dept. of Applied Physics and Physics & CRISP (NSF MRSEC) Ismail-Beigi, Phys. Rev. B (2010)

More information

RPA in infinite systems

RPA in infinite systems RPA in infinite systems Translational invariance leads to conservation of the total momentum, in other words excited states with different total momentum don t mix So polarization propagator diagonal in

More information

X-ray absorption at the L 2,3 edge of an anisotropic single crystal: Cadmium 0001

X-ray absorption at the L 2,3 edge of an anisotropic single crystal: Cadmium 0001 PHYSICAL REVIEW B VOLUME 54, NUMBER 4 5 JULY 996-II X-ray absorption at the L 2,3 edge of an anisotropic single crystal: Cadmium 000 P. Le Fèvre Laboratoire pour l Utilisation du Rayonnement Electromagnetique

More information

XAS analysis on nanosystems

XAS analysis on nanosystems XAS analysis on nanosystems Félix Jiménez-Villacorta Spanish CRG Beamline (SpLine) ESRF XLIV Zakopane School of Physics Breaking Frontiers: Submicron Structures in Physics and Biology May-2009 1 XAS analysis

More information

Atomic XAFS as a Probe of Charge Redistribution within Organometallic Complexes

Atomic XAFS as a Probe of Charge Redistribution within Organometallic Complexes Atomic XAFS as a Probe of Charge Redistribution within Organometallic Complexes Abstract The Atomic XAFS contributions in the Pt L2,3 X-ray absorption fine structure spectra (XAFS) of [PtCl(NCN)-Z] pincer

More information

Chapter 1 Introduction to X-Ray Absorption Spectroscopy

Chapter 1 Introduction to X-Ray Absorption Spectroscopy Chapter 1 Introduction to X-Ray Absorption Spectroscopy Claudia S. Schnohr and Mark C. Ridgway X-ray Absorption Spectroscopy (XAS) is a well-established analytical technique used extensively for the characterization

More information

Spectroscopies for Unoccupied States = Electrons

Spectroscopies for Unoccupied States = Electrons Spectroscopies for Unoccupied States = Electrons Photoemission 1 Hole Inverse Photoemission 1 Electron Tunneling Spectroscopy 1 Electron/Hole Emission 1 Hole Absorption Will be discussed with core levels

More information

Using synchrotron radiation to study catalysis

Using synchrotron radiation to study catalysis Using synchrotron radiation to study catalysis Carlo Segre Physics Department & Center for Synchrotron Radiation Research and Instrumentation Illinois Institute of Technology March 18, 2014 Illinois Institute

More information

Electronic structure of correlated electron systems. Lecture 2

Electronic structure of correlated electron systems. Lecture 2 Electronic structure of correlated electron systems Lecture 2 Band Structure approach vs atomic Band structure Delocalized Bloch states Fill up states with electrons starting from the lowest energy No

More information

The electronic structure of materials 1

The electronic structure of materials 1 Quantum mechanics 2 - Lecture 9 December 18, 2013 1 An overview 2 Literature Contents 1 An overview 2 Literature Electronic ground state Ground state cohesive energy equilibrium crystal structure phase

More information

Introduction to X-ray Absorption Near Edge Spectroscopy (XANES) Ritimukta Sarangi SSRL, SLAC Stanford University June 28, 2010

Introduction to X-ray Absorption Near Edge Spectroscopy (XANES) Ritimukta Sarangi SSRL, SLAC Stanford University June 28, 2010 Introduction to X-ray Absorption Near Edge Spectroscopy (XANES) Ritimukta Sarangi SSRL, SLAC Stanford University June 28, 2010 Basics of X-ray Absorption Spectroscopy (XAS) An edge results when a core

More information

Basics of EXAFS data analysis. Shelly Kelly Argonne National Laboratory, Argonne, IL

Basics of EXAFS data analysis. Shelly Kelly Argonne National Laboratory, Argonne, IL Basics of EXAFS data analysis Shelly Kelly Argonne National Laboratory, Argonne, IL X-ray-Absorption Fine Structure NSLS monochromator slits Sample I 0 I t Ion Chambers I f Attenuation of x-rays I t =

More information

Structural characterization. Part 1

Structural characterization. Part 1 Structural characterization Part 1 Experimental methods X-ray diffraction Electron diffraction Neutron diffraction Light diffraction EXAFS-Extended X- ray absorption fine structure XANES-X-ray absorption

More information

Structural aspects. Povo (Trento), Italy. 1 Institute of Physics, Academy of Sciences of the Czech Republic, Prague

Structural aspects. Povo (Trento), Italy. 1 Institute of Physics, Academy of Sciences of the Czech Republic, Prague Structural aspects of B K edge XANES of minerals O. Šipr, 1 A. Šimůnek, 1 J. Vackář, 1 F. Rocca, G. Dalba 3 1 Institute of Physics, Academy of Sciences of the Czech Republic, Prague Istituto di Fotonica

More information

Fundamentals of X-ray Absorption Fine Structure

Fundamentals of X-ray Absorption Fine Structure UNDERGRADUATE SUMMER SCHOOL, ESRF, SEPTEMBER 16 Fundamentals of X-ray Absorption Fine Structure Sakura Pascarelli European Synchrotron Radiation Facility, Grenoble, France Page Undergraduate summer school

More information

Chapter 3. The (L)APW+lo Method. 3.1 Choosing A Basis Set

Chapter 3. The (L)APW+lo Method. 3.1 Choosing A Basis Set Chapter 3 The (L)APW+lo Method 3.1 Choosing A Basis Set The Kohn-Sham equations (Eq. (2.17)) provide a formulation of how to practically find a solution to the Hohenberg-Kohn functional (Eq. (2.15)). Nevertheless

More information

High pressure core structures of Si nanoparticles for solar energy conversion

High pressure core structures of Si nanoparticles for solar energy conversion High pressure core structures of Si nanoparticles for solar energy conversion S. Wippermann, M. Vörös, D. Rocca, A. Gali, G. Zimanyi, G. Galli [Phys. Rev. Lett. 11, 4684 (213)] NSF/Solar DMR-135468 NISE-project

More information

Minimal Update of Solid State Physics

Minimal Update of Solid State Physics Minimal Update of Solid State Physics It is expected that participants are acquainted with basics of solid state physics. Therefore here we will refresh only those aspects, which are absolutely necessary

More information

FEFF8. The FEFF Project Department of Physics University of Washington

FEFF8. The FEFF Project Department of Physics University of Washington FEFF8 The FEFF Project Department of Physics University of Washington version 8.20 21 May, 2002 Abstract Ab initio self-consistent real space multiple-scattering code for simultaneous calculations of x-ray-absorption

More information

An introduction to the dynamical mean-field theory. L. V. Pourovskii

An introduction to the dynamical mean-field theory. L. V. Pourovskii An introduction to the dynamical mean-field theory L. V. Pourovskii Nordita school on Photon-Matter interaction, Stockholm, 06.10.2016 OUTLINE The standard density-functional-theory (DFT) framework An

More information

Reviewers' comments: Reviewer #1 (Remarks to the Author):

Reviewers' comments: Reviewer #1 (Remarks to the Author): Reviewers' comments: Reviewer #1 (Remarks to the Author): The work is very interesting as it presents a way to reduce the ohmic losses in the metals in the finite range of frequencies. In this the work

More information

Angle-Resolved Two-Photon Photoemission of Mott Insulator

Angle-Resolved Two-Photon Photoemission of Mott Insulator Angle-Resolved Two-Photon Photoemission of Mott Insulator Takami Tohyama Institute for Materials Research (IMR) Tohoku University, Sendai Collaborators IMR: H. Onodera, K. Tsutsui, S. Maekawa H. Onodera

More information

Electronic structure of solids: basic concepts and methods

Electronic structure of solids: basic concepts and methods Electronic structure of solids: basic concepts and methods Ondřej Šipr II. NEVF 514 Surface Physics Winter Term 2016-2017 Troja, 21st October 2016 Outline A bit of formal mathematics for the beginning

More information