<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <p>The title compound is synthesized from stoichiometric mixtures of BaO<sub>2</sub>, Os, and Nd<sub>2</sub>O<sub>3</sub> (Pt crucible, Ag<sub>2</sub>O as oxygen donor in a second Pt crucible, 1270 K, 6 h).</p> </abstract>