@article{BornJohanssonLeitneretal.2022,
  author    = {Born, Artur and Johansson, Fredrik O. L. and Leitner, Torsten and Bidermane, Ieva and Kuehn, Danilo and Martensson, Nils and F{\"o}hlisch, Alexander},
  title     = {The degree of electron itinerancy and shell closing in the core-ionized state of transition metals probed by Auger-photoelectron coincidence spectroscopy},
  series = {Physical chemistry, chemical physics : a journal of European Chemical Societies},
  volume    = {24},
  journal   = {Physical chemistry, chemical physics : a journal of European Chemical Societies},
  number    = {32},
  publisher = {Royal Society of Chemistry},
  address   = {Cambridge},
  issn      = {1463-9076},
  doi       = {10.1039/d2cp02477b},
  pages     = {19218 -- 19222},
  year      = {2022},
  abstract  = {Auger-photoelectron coincidence spectroscopy (APECS) has been used to examine the electron correlation and itinerance effects in transition metals Cu, Ni and Co. It is shown that the LVV Auger, in coincidence with 2p photoelectrons, spectra can be represented using atomic multiplet positions if the 3d-shell is localized (atomic-like) and with a self-convoluted valence band for band-like (itinerant) materials as explained using the Cini-Sawatzky model. For transition metals, the 3d band changes from band-like to localized with increasing atomic number, with the possibility of a mixed behavior. Our result shows that the LVV spectra of Cu can be represented by atomic multiplet calculations, those of Co resemble the self-convolution of the valence band and those of Ni are a mixture of both, consistent with the Cini-Sawatzky model.},
  language  = {en}
}
@article{PochIstiqomahQuiricoetal.2020,
  author    = {Poch, Olivier and Istiqomah, Istiqomah and Quirico, Eric and Beck, Pierre and Schmitt, Bernard and Theul{\´e}, Patrice and Faure, Alexandre and Hily-Blant, Pierre and Bonal, Lydie and Kappel, David},
  title     = {Ammonium salts are a reservoir of nitrogen on a cometary nucleus and possibly on some asteroids},
  series = {Science},
  volume    = {367},
  journal   = {Science},
  number    = {6483},
  publisher = {AAAS, American Association for the Advancement of Science},
  address   = {Washington, DC},
  issn      = {1095-9203},
  doi       = {10.1126/science.aaw7462},
  pages     = {1 -- 8},
  year      = {2020},
  abstract  = {The measured nitrogen-to-carbon ratio in comets is lower than for the Sun, a discrepancy which could be alleviated if there is an unknown reservoir of nitrogen in comets. The nucleus of comet 67P/Churyumov-Gerasimenko exhibits an unidentified broad spectral reflectance feature around 3.2 micrometers, which is ubiquitous across its surface. On the basis of laboratory experiments, we attribute this absorption band to ammonium salts mixed with dust on the surface. The depth of the band indicates that semivolatile ammonium salts are a substantial reservoir of nitrogen in the comet, potentially dominating over refractory organic matter and more volatile species. Similar absorption features appear in the spectra of some asteroids, implying a compositional link between asteroids, comets, and the parent interstellar cloud.},
  language  = {en}
}