@article{PetitgirardSahleWeisetal.2019,
  author    = {Petitgirard, Sylvian and Sahle, C. J. and Weis, C. and Gilmore, K. and Spiekermann, Georg and Tse, J. S. and Wilke, Max and Cavallari, C. and Cerantola, V and Sternemann, Christian},
  title     = {Magma properties at deep Earth's conditions from electronic structure of silica},
  series = {Geochemical perspectives letters},
  volume    = {9},
  journal   = {Geochemical perspectives letters},
  publisher = {Association of Geochemistry},
  address   = {Paris},
  issn      = {2410-339X},
  doi       = {10.7185/geochemlet.1902},
  pages     = {32 -- 37},
  year      = {2019},
  abstract  = {SiO(2 )is the main component of silicate melts and thus controls their network structure and physical properties. The compressibility and viscosities of melts at depth are governed by their short range atomic and electronic structure. We measured the O K-edge and the Si L-2,L-3-edge in silica up to 110 GPa using X-ray Raman scattering spectroscopy, and found a striking match to calculated spectra based on structures from molecular dynamic simulations. Between 20 and 27 GPa, Si-[4] species are converted into a mixture of Si-[5] and Si-[6] species and between 60 and 70 GPa, Si-[6] becomes dominant at the expense of Si-[5] with no further increase up to at least 110 GPa. Coordination higher than 6 is only reached beyond 140 GPa, corroborating results from Brillouin scattering. Network modifying elements in silicate melts may shift this change in coordination to lower pressures and thus magmas could be denser than residual solids at the depth of the core-mantle boundary.},
  language  = {en}
}
@article{KetenogluSpiekermannHarderetal.2018,
  author    = {Ketenoglu, Didem and Spiekermann, Georg and Harder, Manuel and Oz, Erdinc and Koz, Cevriye and Yagci, Mehmet C. and Yilmaz, Eda and Yin, Zhong and Sahle, Christoph J. and Detlefs, Blanka and Yavas, Hasan},
  title     = {X-ray Raman spectroscopy of lithium-ion battery electrolyte solutions in a flow cell},
  series = {Journal of synchrotron radiation},
  volume    = {25},
  journal   = {Journal of synchrotron radiation},
  publisher = {International Union of Crystallography},
  address   = {Chester},
  issn      = {0909-0495},
  doi       = {10.1107/S1600577518001662},
  pages     = {537 -- 542},
  year      = {2018},
  abstract  = {The effects of varying LiPF6 salt concentration and the presence of lithium bis(oxalate)borate additive on the electronic structure of commonly used lithium-ion battery electrolyte solvents (ethylene carbonate-dimethyl carbonate and propylene carbonate) have been investigated. X-ray Raman scattering spectroscopy (a non-resonant inelastic X-ray scattering method) was utilized together with a closed-circle flow cell. Carbon and oxygen K-edges provide characteristic information on the electronic structure of the electrolyte solutions, which are sensitive to local chemistry. Higher Li+ ion concentration in the solvent manifests itself as a blue-shift of both the pi* feature in the carbon edge and the carbonyl pi* feature in the oxygen edge. While these oxygen K-edge results agree with previous soft X-ray absorption studies on LiBF4 salt concentration in propylene carbonate, carbon K-edge spectra reveal a shift in energy, which can be explained with differing ionic conductivities of the electrolyte solutions.},
  language  = {en}
}