<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <p>The title compounds are prepared by solid state reaction of NiO, Sc<sub>2</sub>O<sub>3</sub> or In<sub>2</sub>O<sub>3</sub>, and Sb<sub>2</sub>O<sub>5</sub> (1300 °C, 24 h).</p> </abstract>