부산대학교 도서관

In our attempt to search for mixed alkaline-earth and transition metal arsenates, the title compound, barium dimanganese(II) bis(arsenate), has been synthesized by employing a high-temperature RbCl flux. The crystal structure of BaMn2(AsO4)2 is made up of MnO6 octahedra and AsO4 tetrahedra assembled by sharing corners and edges into infinite slabs with composition [Mn2(AsO4)2]2− that extend parallel to the ab plane. The barium cations reside between parallel slabs maintaining the interslab connectivity through coordination to eight oxygen anions. The layered anionic framework comprises weakly interacting [Mn4O18]28− tetrameric units. In each tetramer, the manganese(II) cations are in a planar arrangement related by a center of inversion. Within the slabs, the tetrameric units are separated from each other by 6.614 (2) Å (Mn...Mn distances). The title compound has isostructural analogues amongst synthetic SrM2(XO4)2 compounds with M = Ni, Co, and X = As, P.