460 Pages 9 Color & 325 B/W Illustrations
    by CRC Press

    XAFS for Everyone provides a practical, thorough guide to x-ray absorption fine-structure (XAFS) spectroscopy for both novices and seasoned practitioners from a range of disciplines. The text is enhanced with more than 200 figures as well as cartoon characters who offer informative commentary on the different approaches used in XAFS spectroscopy.

    The book covers sample preparation, data reduction, tips and tricks for data collection, fingerprinting, linear combination analysis, principal component analysis, and modeling using theoretical standards. It describes both near-edge (XANES) and extended (EXAFS) applications in detail. Examples throughout the text are drawn from diverse areas, including materials science, environmental science, structural biology, catalysis, nanoscience, chemistry, art, and archaeology. In addition, five case studies from the literature demonstrate the use of XAFS principles and analysis in practice. The text includes derivations and sample calculations to foster a deeper comprehension of the results.

    Whether you are encountering this technique for the first time or looking to hone your craft, this innovative and engaging book gives you insight on implementing XAFS spectroscopy and interpreting XAFS experiments and results. It helps you understand real-world trade-offs and the reasons behind common rules of thumb.

    The XAFS Experiment
    XAFS in a Nutshell

    X-Ray Absorption Spectra
    Basics of EXAFS Theory
    Some Terminology
    Data Reduction
    XAFS Is Not a Black Box
    Overview of Approaches to XAFS
    Analysis

    Planning the Experiment
    Identifying Your Questions
    Synchrotron Light Sources
    Bending Magnets and Insertion Devices
    Monochromators (and Polychromators)
    Measurement Modes and Detectors
    Experimental Design
    Getting Beamtime

    Sample Preparation
    XAFS Samples
    Absorption
    Sample Characteristics for Transmission
    Sample Characteristics for Fluorescence
    Sample Considerations for Electron Yield Experiments
    Which Technique Should You Choose?
    Preparing Samples

    Data Reduction
    Preprocessing
    Calibration and Alignment
    Finding Normalized Absorption
    Finding χ(k)
    Finding the Fourier Transform

    Data Collection
    Noise, Distortion, and Time
    Detector Choice
    Before You Begin
    Optimizing the Beam
    Ion Chambers
    Suppressing Fluorescent Background
    Aligning the Sample
    Scan Parameters
    "What’s That?"

    XAFS Analysis
    Fingerprinting

    Matching Empirical Standards
    Fingerprinting Spectral Features
    Semiquantitative Fingerprinting
    Theoretical XANES Standards

    Linear Combination Analysis
    When LCA Works
    When LCA Doesn’t Work
    An Example of LCA
    Statistics of Linear Combination Fitting
    Combinatoric Fitting
    Sources of Systematic Error
    Choosing Data Range and Space for LCA

    Principal Component Analysis
    Introduction
    The Idea of PCA
    How Many Components?
    How Many Constituents?
    PCA Formalism
    Cluster Analysis
    Target Transforms
    PCA of EXAFS
    How PCA Is Used
    Future Developments

    Curve Fitting to Theoretical Standards
    Fitting
    Theoretical Standards
    The Path Expansion
    Fitting Strategies

    Modeling
    A Dictionary of Parameters

    Common Fitting Parameters
    Less Common Fitting Parameters
    Scattering Parameters

    Identifying a Good Fit
    Criterion 1: Statistical Quality
    Criterion 2: Closeness of Fit
    Criterion 3: Precision
    Criterion 4: Size of Data Ranges
    Criterion 5: Agreement outside the Fitted Range
    Criterion 6: Stability
    Criterion 7: Are the Results Physically Possible?
    Criterion 8: How Defensible Is the Model?
    Evaluating a Fit

    The Process of Fitting
    Identify Your Questions
    Prepare Your Data
    Plan Your Strategy
    Fit!

    Starting Structures
    Crystal Structures
    Calculated Structures
    Mixtures
    Inequivalent Absorbing Sites
    Histogram Methods
    Multiple-Edge Fits
    Site Occupancy

    Constraints
    Rigorous Constraints
    Constraints Based on a Priori Knowledge
    Constraints for Simplification
    Some Special Cases
    Multiple-Scattering Paths
    Alternatives for Incorporating a Priori Knowledge

    XAFS in the Literature
    Communicating XAFS
    Know Your Audience
    Experimental Details
    Data
    Data Reduction
    Models and Standards
    Results
    Conclusions

    Case Studies
    Introduction to the Case Studies
    Lead Titanate, a Ferroelectric
    An Iron–Molybdenum Cofactor Precursor
    Manganese Zinc Ferrite, an Example of Fitting Site Occupancy
    Sulfur XANES from the Wreck of the Mary Rose
    Identification of Manganese-Based Particulates in Automobile Exhaust
    The Next Case Study: Yours

    Appendix

    Index

    References appear at the end of each chapter.

    Biography

    Scott Calvin is the chair of the Division of Natural Science and Mathematics at Sarah Lawrence College, where he teaches innovative courses, including crazy ideas in physics, rocket science, and steampunk physics. He is also a member of the principal research team for beamline X-11B at the National Synchrotron Light Source. Since 1998, he has been using XAFS to study systems as diverse as solar cells, magnetic nanoparticles, soil samples, battery cathodes, analogues to atmospheric dust particles, and pigments used in 18th century painting. He received a PhD in physics from Hunter College of the City University of New York.

    "The book is very timely … It is unique in covering theoretical background and experimental details to data analysis in a way that is easy to understand. It will be very valuable to anyone who is interested in using x-ray spectroscopy by helping them to better design and get more out of their experiments."
    —Dr. Chi-Chang Kao, Director, SLAC National Accelerator Laboratory

    "The author has found fun and engaging ways to explain details of XAFS that otherwise can seem so dry. I am sure that folks who use my beamline and software will love XAFS for Everyone."
    —Dr. Bruce Ravel, National Institute of Standards and Technology

    "A unique presentation with great value for readers and special emphasis on practical aspects … a ‘must have’ for XAFS scientists and beamlines."
    —Prof. Mark C. Ridgway, Department of Electronic Materials Engineering, Australian National University

    "This book will be useful to graduate students, post docs, and researchers. I highly recommend it."
    —Dr. Richard W. Strange, Molecular Biophysics, The University of Liverpool