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SOFTWARE

OCEAN

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.

Uses

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

Bethe-Salpeter equation calculations of core excitation spectra, Phys. Rev. B 83, 115106 (2011)
Efficient implementation of core-excitation Bethe–Salpeter equation calculations, Comp. Phys. Comm. 197, 109 (2015)
Advances in the OCEAN-3 spectroscopy package, Physical. Chem. Chem. Physical. 24, 12787 (2022)

Recent OCEAN papers

Local Structure of Sulfur Vacancies on the Basal Plane of Monolayer MoS₂, ACS Nano 16, 6725 (2022)
Origin of enhanced water oxidation activity in an iridium single atom anchored on NiFe oxyhydroxide catalyst, PNAS 118 e2101817118 (2021)
Database of ab initio L-edge X-ray absorption near edge structure, Scientific Data 8, 153 (2021)
Revealing Electronic Signatures of Lattice Oxygen Redox in Lithium Ruthenates and Implications for High-Energy Li-Ion Battery Material Designs, Chem. Mater. 31, 7864 (2019)
Resonant x-ray emission and valence-band lifetime broadening in LiNO3, Phys. Rev. B 100, 085143 (2019)
Spectroscopic Signature of Oxidized Oxygen States in Peroxides, J. Phys. Chem. Lett. 9, 6378 (2018)

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.