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Theoretical X-ray Absorption Spectroscopy of Liquid Water by the GW plus Bethe-Salpeter equation (GW-BSE) method

ORAL

Abstract

Oxygen K-edge x-ray absorption spectroscopy (XAS) provides an important local probe of the H-bond network in liquid water. Theoretical calculations of XAS spectra demand accurate modeling of both the molecular structure and the electron-hole excitation process. We generate the water structure from path-integral DeePMD calculations, whose neural network potential is trained on state-of-the-art DFT data at the SCAN0 hybrid functional level. Based on the above equilibrated trajectory, the XAS spectra of liquid water are computed by solving the Bethe-Salpeter equation (BSE) as implemented in the BerkeleyGW package. Our calculated XAS spectra of water agree well with experiments. Our results indicate that self-consistent GW quasiparticle wavefunctions and local-fields effects in electronic screening are crucial in the GW-BSE approach in order to yield XAS spectra that are in quantitative agreement with experiments.

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Presenters

  • Fujie Tang

    Department of physics, Temple University

Authors

  • Fujie Tang

    Department of physics, Temple University

  • Chunyi Zhang

    Department of physics, Temple University, Temple University

  • Zhenglu Li

    Department of Physics, University of California, Berkeley, UC Berkeley & Lawrence Berkeley National Laboratory, University of California at Berkeley, and Lawrence Berkeley National Laboratory, University of California at Berkeley and Lawrence Berkeley National Laboratory, Lawrence Berkeley National Laboratory, University of California, Berkeley, Lawrence Berkeley National Laboratory and University of California at Berkeley, Department of physics, University of California at Berkeley, Berkeley, California

  • Steven G Louie

    University of California, Berkeley, Department of Physics, University of California, Berkeley, University of California at Berkeley and Lawrence Berkeley National Laboratory, UC Berkeley & Lawrence Berkeley National Laboratory, University of California at Berkeley, and Lawrence Berkeley National Laboratory, Lawrence Berkeley National Laboratory, Department of physics, University of California at Berkeley, Berkeley, California

  • Roberto Car

    Department of Chemistry, Princeton University, Princeton University, Department of Chemistry, Princeton University, Princeton, NJ 08544, USA

  • Diana Qiu

    Yale University, Department of Mechanical Engineering and Materials Science, Yale University, Mechanical Engineering and Materials Science, Yale University, School of Engineering and Applied Physics, Yale University

  • Xifan Wu

    Department of physics, Temple University, Temple University