Views Navigation

Event Views Navigation

Today

Frank deGroot: Transition metal K edge spectral shapes: The influence of core hole screening

Using High-Energy-Resolution-Fluorescence-Detection (HERFD), one can sharpen the pre-edge structures revealing their multiplet nature. In ionic systems, they can be calculated from the transition from the 3dN ground state to the 1s13dN+1 final state, where covalent systems need the inclusion of charge transfer effects. The main edge is usually interpreted from the calculation of the transitions […]

Faisal Alamgir: Soft and Hard X-ray Operando and In/Ex-situ XAFS: Towards a Unified View of Local Structure and Magnetic Properties in LiMO2 Delafossite Batteries

We will look at how electrochemically active materials such as batteries can be studied in a concerted way by tuning to relevant resonant x-ray absorption at both the soft and the hard x-ray energy regimes. We will specifically examine the role of oxygen in the charge compensation of LiMO2 delafossite compounds, that serve as cathodes […]

Paul Northrup: The TES Beamline (8-BM) at NSLS-II: tender-energy spatially-resolved X-ray absorption spectroscopy and X-ray fluorescence imaging

I will present details of the TES Beamline at the National Synchrotron Light Source II, covering its design, commissioning, and early results. Its scientific mission includes static and in-situ/operando XRF imaging and spatially resolved (microbeam) XAS -- in the tender energy range -- for characterization of complex heterogeneous, structured and dynamic natural or engineered materials […]

John Rehr: Fast throughput calculations and the XAFS data base in the Materials Project

Modern electronic structure theory and computational methods now permit efficient calculations of ground state properties, as exemplified by the tabulation of many-thousands of structures in the Materials Project . Complementary advances in the theory of excited states have led to efficient methods for calculations of x-ray and electron spectroscopies, e.g., using the real-space Green's multiple […]

Pieter Glatzel: Reflections on hard X-ray photon-in/photon-out spectroscopy

The presentation will be a collection of thoughts that I find interesting for the experimentalist employing hard X-ray photon-in/photon-out spectroscopy with a wavelength dispersive instrument. I would like to draw the attention to some experimental aspects and will give hopefully useful advice that may be considered for the experimental protocol. Furthermore, I will present the […]

Jennifer Mass: MicroXANES studies of pigment degradation in works by Henri Matisse and a Dutch golden age still life

The new painting materials used by the Impressionists, Fauvists, and Expressionists were critical components of their break with traditional modes of representation. These artists heavily exploited the synthetic organic and inorganic pigments that were newly available as a result of the industrial revolution. However, the bright and novel hues that made their way onto these […]

Jason Shearer: Structural Determination of Small Molecular Systems Using a Wavelet Analysis

Presented will be a discussion of efforts to employ a wavelet transform (WT) analysis towards the quantitative structural determination of discrete molecular systems using an EXAFS analysis. Unlike a transition Fourier transform (FT) analysis, a WT analysis yields a 2D plot in both k- and R-space. Thus, information contained in k-space that can be lost […]

Joshua Kas: Corvus: A Workflow Tool for X-ray and Related Spectroscopies

Great strides have been made over the past decade in the theory and calculation of X-ray and related spectra. Some advances involve predictions of material properties such as structure or dynamics in order to make a prediction more complete, thus requiring less input, or otherwise reducing the number of free parameters required to fit to […]

Megan Holycross: Probing the deep Earth oxygen cycle with XANES

The oxidation state of the solid Earth influences, to a first order, the structure of the planet and the chemistry of rocks, ores and volcanic gases; mass transfer of oxygen between terrestrial reservoirs enables a habitable world. Fe K-edge XANES spectroscopy shows magmas erupted from continental crust, formed at subduction zones, are more oxidized than […]

Jerry Seidler: Overview of lab XAFS/XES

After decades of relative silence, lab-based spectroscopy has made a comeback in recent years. Modern spectrometers have energy resolution comparable to synchrotron XAS beamlines and have performances demonstrated in dozens of recent publications. Here, I will briefly summarize the various technical approaches before focusing on examples for XAFS and XES in the hard and tender […]