Abstract: | Na5Nb05 and Na5Ta05 Phases. Crystal Structure of Na5NbO5 New ternary oxides of formulas Na5NbO5 and Na5TaO5 have been prepared. They crystallize in the monoclinic system (space group C2/c). The crystal structure of Na5NbO5 has been determined. It derives from a NaCl-type structure by ordering of the cations and of the oxygen vacancies in the anionic sublattice, the corresponding formula being Na5/6Nb1/6O5/6□1/6. Sodium and niobium have a distorted square-pyramidal surrounding. |