1
|
|
2
|
Woicik JC, Weiland C, Rumaiz AK, Brumbach MT, Ablett JM, Shirley EL, Kas JJ, Rehr JJ. Core hole processes in x-ray absorption and photoemission by resonant Auger-electron spectroscopy and first-principles theory. PHYSICAL REVIEW. B 2020; 101:10.1103/physrevb.101.245105. [PMID: 34409241 PMCID: PMC8370031 DOI: 10.1103/physrevb.101.245105] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Electron-core hole interactions are critical for proper interpretation of core-level spectroscopies commonly used as analytical tools in materials science. Here we utilize resonant Auger-electron spectroscopy to uniquely identify exciton, shake, and charge-transfer processes that result from the sudden creation of the core hole in both x-ray-absorption and photoemission spectra. These effects are captured for the transition-metal compounds SrTiO3 and MoS2 by fully ab initio, combined real-time cumulant, and Bethe-Salpeter equation approaches to account for core hole dynamics and screening. Atomic charges and excited-state electron-density fluctuations reflect materials' solid-state electronic structure, loss of translational symmetry around the core hole, and breakdown of the sudden approximation. They also demonstrate competition between long- and short-range screening in a solid.
Collapse
Affiliation(s)
- J C Woicik
- Material Measurement Science Division, Material Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
| | - C Weiland
- Material Measurement Science Division, Material Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
| | - A K Rumaiz
- National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, New York 11973, USA
| | - M T Brumbach
- Materials Characterization Department, Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - J M Ablett
- Synchrotron SOLEIL, L'Orme des Merisiers, Saint-Aubin, 91192 Gif-sur-Yvette Cedex, France
| | - E L Shirley
- Sensor Science Division, Physical Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
| | - J J Kas
- Department of Physics, University of Washington, Seattle, Washington 98195, USA
| | - J J Rehr
- Department of Physics, University of Washington, Seattle, Washington 98195, USA
| |
Collapse
|
3
|
Woicik JC, Weiland C, Jaye C, Fischer DA, Rumaiz AK, Shirley EL, Kas JJ, Rehr JJ. Charge-transfer satellites and chemical bonding in photoemission and x-ray absorption of SrTiO 3 and rutile TiO 2: Experiment and first-principles theory with general application to spectroscopic analysis. PHYSICAL REVIEW. B 2020; 101:10.1103/physrevb.101.245119. [PMID: 34409240 PMCID: PMC8370030 DOI: 10.1103/physrevb.101.245119] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
First-principles, real-time-cumulant, and Bethe-Salpeter-equation calculations fully capture the detailed satellite structure that occurs in response to the sudden creation of the core hole in both photoemission and x-ray absorption spectra of the transition-metal compounds SrTiO3 and rutile TiO2. Analysis of the excited-state, real-space charge-density fluctuations betrays the physical nature of these many electron excitations that are shown to reflect the materials' solid-state electronic structure and chemical bonding. This first-principles development of the cumulant-based core hole spectral function is generally applicable to other systems and should become a standard tool for all similar spectroscopic analysis going beyond the quasiparticle physics of the photoelectric effect.
Collapse
Affiliation(s)
- J C Woicik
- Materials Measurement Science Division, Material Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
| | - C Weiland
- Materials Measurement Science Division, Material Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
| | - C Jaye
- Materials Measurement Science Division, Material Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
| | - D A Fischer
- Materials Measurement Science Division, Material Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
| | - A K Rumaiz
- National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, New York 11973, USA
| | - E L Shirley
- Sensor Science Division, Physical Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
| | - J J Kas
- Department of Physics, University of Washington, Seattle, Washington 98195, USA
| | - J J Rehr
- Department of Physics, University of Washington, Seattle, Washington 98195, USA
| |
Collapse
|
4
|
Abstract
The multiplet theory of free ions combined with crystal field theory is used to study core electron excitation of perovskites. This combined method is helpful to further identify transition peaks and comprehend the transition mechanism. In this paper, the core electron excitation of Ti K edge, L2,3 edges, and M edge in SrTiO3 and PbTiO3 is studied, and the identification of peak and the analysis of spectral shape are emphasized. Especially at the M edge, we can identify the dipole and higher-order multiple transition peaks of Ti4+. At the L2,3 edges, the transition strength corresponding to the 2p3d configuration coupling affects the shape of the spectra. The correction of the crystal field can make the theoretical spectra more consistent with the experimental spectra. For the K edge in PbTiO3, by comparing the spectral shapes and energy of Ti2+, Ti3+, and Ti4+ with experiments, the spectrum is mainly composed of Ti3+ and Ti4+, and the proportion of Ti4+ is determined to be over 91%.
Collapse
Affiliation(s)
- Qi Zhao
- Institute of Atomic and Molecular Physics , Sichuan University , Chengdu 610065 , China
| | - Xin-Lu Cheng
- Institute of Atomic and Molecular Physics , Sichuan University , Chengdu 610065 , China
| |
Collapse
|
5
|
Wansleben M, Vinson J, Wählisch A, Bzheumikhova K, Hönicke P, Beckhoff B, Kayser Y. Speciation of iron sulfide compounds by means of X-ray Emission Spectroscopy using a compact full-cylinder von Hamos spectrometer. JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY 2020; 35:10.1039/d0ja00244e. [PMID: 34092880 PMCID: PMC8176736 DOI: 10.1039/d0ja00244e] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
We present experimental and theoretical X-ray emission spectroscopy (XES) data of the Fe Kβ line for Iron(II)sulfide (FeS) and Iron(II)disulfide (FeS2). In comparison to X-ray absorption spectroscopy (XAS), XES offers different discrimination capabilities for chemical speciation, depending on the valence states of the compounds probed and, more importantly in view of a a broader, laboratory-based use, a larger flexibility with respect to the excitation source used. The experimental Fe Kβ XES data was measured using polychromatic X-ray radiation and a compact full-cylinder von Hamos spectrometer while the calculations were realized using the OCEAN code. The von Hamos spectrometer used is characterized by an energy window of up to 700 eV and a spectral resolving power of E/ΔE = 800. The large energy window at a single position of the spectrometer components is made profit of to circumvent the instrumental sensitivity of wavelength-dispersive spectrometers to sample positioning. This results in a robust energy scale which is used to compare experimental data with ab initio valence-to-core calculations, which are carried out using the ocean package. To validate the reliability of the ocean package for the two sample systems, near edge X-ray absorption fine structure measurements of the Fe K absorption edge are compared to theory using the same input parameters as in the case of the X-ray emission calculations. Based on the example of iron sulfide compounds, the combination of XES experiments and ocean calculations allows unravelling the electronic structure of different transition metal sulfides and qualifying XES investigations for the speciation of different compounds.
Collapse
Affiliation(s)
- Malte Wansleben
- Physikalisch-Technische Bundesanstalt, Abbestraße 2-12, 10587 Berlin, Germany
- Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Hahn-Meitner-Platz 1, 14109 Berlin, Germany
| | - John Vinson
- National Institute of Standards and Technology, Gaithersburg, MD 20899, USA
| | - André Wählisch
- Physikalisch-Technische Bundesanstalt, Abbestraße 2-12, 10587 Berlin, Germany
| | - Karina Bzheumikhova
- Physikalisch-Technische Bundesanstalt, Abbestraße 2-12, 10587 Berlin, Germany
| | - Philipp Hönicke
- Physikalisch-Technische Bundesanstalt, Abbestraße 2-12, 10587 Berlin, Germany
| | - Burkhard Beckhoff
- Physikalisch-Technische Bundesanstalt, Abbestraße 2-12, 10587 Berlin, Germany
| | - Yves Kayser
- Physikalisch-Technische Bundesanstalt, Abbestraße 2-12, 10587 Berlin, Germany
| |
Collapse
|