Filled skutterudite structure of europium ruthenium polyphosphide, EuRu ₄P ₁₂

Abstract

The crystal structure of EuRu ₄P ₁₂ is isotypic with filled skutterudite structures of rare earth transition metal poly­phosphides: RFe ₄P ₁₂ ( R = Ce, Pr, Nd, Sm and Eu), RRu ₄P ₁₂ ( R = La, Ce, Pr and Nd) and ROs ₄P ₁₂ ( R = La, Ce, Pr and Nd). The Ru cation is coordinated by six P anions in a distorted octa­hedral manner. The partially occupied Eu position (site occupancy 0.97) is enclosed by a cage formed by the corner-shared framework of the eight RuP ₆ octa­hedra.