Metastability of NbN in the ordered vacancy NbO phase.

نویسندگان

  • Ethridge
  • Erwin
  • Pickett
چکیده

A metastable phase of NbN with superconducting T c =16.4 K was reported recently by Treece and collaborators. The reported structure of the thin film sample deviates from the rocksalt (B1) NbN structure with 25% ordered vacancies on each sublattice (space group Pm3m) and a lattice constant of 4.442Å. Using full potential electronic structure methods, we contrast the electronic structure with that of B1 NbN. The calculated energy, 1.00 eV/molecule higher than B1 NbN, and calculated lattice constant of 4.214Å indicate that the new phase must be something other than the ordered stoichiometric Pm3m phase.

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عنوان ژورنال:
  • Physical review. B, Condensed matter

دوره 52 12  شماره 

صفحات  -

تاریخ انتشار 1995