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Bulk Electronic structure of Na$_{0.35}$CoO$_{2}$.1.3H$_{2}$O

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 نشر من قبل Ashish Chainani
 تاريخ النشر 2003
  مجال البحث فيزياء
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High-energy (h$ u$ = 5.95 keV) synchrotron Photoemission spectroscopy (PES) is used to study bulk electronic structure of Na$_{0.35}$CoO$_{2}$.1.3H$_{2}$O, the layered superconductor. In contrast to 3-dimensional doped Co oxides, Co $it{2p}$ core level spectra show well-separated Co$^{3+}$ and Co$^{4+}$ ions. Cluster calculations suggest low spin Co$^{3+}$ and Co$^{4+}$ character, and a moderate on-site Coulomb correlation energy U$_{dd}sim$3-5.5 eV. Photon dependent valence band PES identifies Co $it{3d}$ and O $it{2p}$ derived states, in near agreement with band structure calculations.



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