Equation of motion coupled-cluster approach for multi-electron excitations in x-ray spectra

ORAL

Abstract

We present a real-time equation of motion coupled cluster approach [1] for calculations of multi-electron excitations in core-level x-ray absorption and emission spectra. Integration of the equations to leading order in particle-hole excitations yields a cumulant representation of the core-hole spectral function. Absorption and emission spectra are then calculated in terms of a convolution of an effective one-body x-ray spectrum and the core-hole spectral function. Comparisons with determinantal approaches and with the Delta-SCF approximation are also discussed. Illustrative calculations are discussed separately [2].
[1] K. Schönhammer and O. Gunnarsson, Phys. Rev. B 18, 6606 (1978).
[2] See F. D. Vila, J. J. Rehr, B. Peng, and K. Kowalski, APS March Meeting 2020.

*Supported by the Center for Scalable, Predictive methods for Excitation and Correlated phenomena (SPEC) which is funded by the U.S. DOE, Office of Science, Basic Energy Sciences, Division of Chemical Sciences, Geosciences, and Biosciences.

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Presenters

  • John Rehr

    • University of Washington

Authors

  • John Rehr

    • University of Washington

  • Fernando Vila

    • University of Washington

  • Joshua Kas

    • University of Washington

  • Karol Kowalski

    • PNNL
    • Pacific Northwest National Laboratory
    • Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory

  • Bo Peng

    • Pacific Northwest National Laboratory