Measurements of ultrafast dissociation in resonant inelastic x-ray scattering of water

Kosuke Yamazoe; Jun Miyawaki; Hideharu Niwa; Anders Nilsson; Yoshihisa Harada

doi:10.1063/1.5081886

Measurements of ultrafast dissociation in resonant inelastic x-ray scattering of water

J Chem Phys. 2019 May 28;150(20):204201. doi: 10.1063/1.5081886.

Authors

Kosuke Yamazoe¹, Jun Miyawaki¹, Hideharu Niwa¹, Anders Nilsson², Yoshihisa Harada¹

Affiliations

¹ Institute for Solid State Physics (ISSP), The University of Tokyo, 5-1-5, Kashiwanoha, Kashiwa, Chiba 277-8581, Japan.
² Department of Physics, AlbaNova University Center, Stockholm University, SE-106 91 Stockholm, Sweden.

PMID: 31153206
DOI: 10.1063/1.5081886

Abstract

There has been a discussion on the interpretation of the resonant inelastic x-ray scattering (RIXS) spectra of liquid water in terms of either different structural environments or that core hole dynamics can generate well-resolved dissociative spectral components. We have used RIXS with high resolution in the OH stretch vibration energy part, at extremely high overtones going toward the continuum of full OH bond breakage, to identify the amount of dissociative contributions in the valence band RIXS spectra at different excitation energies. We observe that at low excitation energies, corresponding to population of states with strongly antibonding character, the valence band RIXS spectra have a large contribution from a well-resolved dissociative feature. Instead, at higher excitations, this spectral component diminishes and becomes a weak structure on the high-energy side of one of the spectral peaks related to the 1b₁ state from tetrahedral configurations. This result brings both interpretations to be essential for the understanding of RIXS spectra of liquid water.