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Dimerization-Induced Cross-Layer Quasi-Two-Dimensionality in Metallic Iridate IrTe2

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 نشر من قبل V. Kiryukhin
 تاريخ النشر 2013
  مجال البحث فيزياء
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The crystal structure of layered metal IrTe2 is determined using single-crystal x-ray diffraction. At T=220 K, it exhibits Ir and Te dimers forming a valence-bond crystal. Electronic structure calculations reveal an intriguing quasi-two-dimensional electronic state, with planes of reduced density of states cutting diagonally through the Ir and Te layers. These planes are formed by the Ir and Te dimers, which exhibit a signature of covalent bonding character development. Evidence for significant charge disproportionation among the dimerized and non-dimerized Ir (charge order) is also presented.

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