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The measured and calculated RIXS maps at the oxygen K edge of lithium peroxide

OCEAN is a versatile package for calculating both optical/UV and core-edge spectroscopy. It is a first-principles code based on both ground-state density-functional theory (DFT) and the Bethe-Salpeter equation (BSE).

On the right is shown the resonant inelastic x-ray scattering spectra of lithium peroxide as measured in experiment and calculated using OCEAN. The circled feature was identified as a fingerprint of oxygen oxidation in this system


OCEAN is capable of calculating a variety of spectra, including:

  • X-ray absorption spectra (XAS)
  • Non-resonant inelastic x-ray scattering (NRIXS) also called x-ray Raman scattering (XRS)
  • Resonant inelastic x-ray scattering (RIXS)
  • Optical/UV absorption
  • Electron energy loss spectroscopy (EELS)


Main OCEAN Publications

Recent OCEAN papers


NRC postdoc positions

Postdoc positions at NIST are available through the National Academies. Specific listings are here and here, and more general information can be found here.

Created November 24, 2020, Updated May 3, 2023