文档介绍：Manganese oxide tunnel structures determined with TEM J. Hadermann a, . Abakumov b, L. Gillie c, O. Perez c , C. Martin c, M. Hervieu c, G. Van Tendeloo a aEMAT, University of Antwerp, Belgium, bMoscow State University, Russia, RSCaen, France. E-mail: joke.******@ Keywords: structure determination, transmission electron microscopy, mensurate plex manganese oxides A x MnO 2 (x <1) show a tendency to plex tunnel structures. The major structural unit of the tunnel walls is a rutile-type chain of edge sharing MnO 6 octahedra. A variety of structures arises due to the ability of these chains to form double and triple chain blocks by sharing octahedral edges. We will present the structure determination of three such pounds with approximately the same A/Mnratio, SrMn 3 O 6[1], CaMn 3 O 6and Sr Mn 3 (O,F) 6, where the shape of the channels and the ordering pattern of the A-cations vary. We have solved their structures with trans- mission electron microscopy (TEM) and then refined them from XRDand/or NPDdata. The HREMimages taken along the direction of the tunnel propagation clearly show that the pounds have different shapes of tunnels. In the case of SrMn 3 O 6the tunnel structure is of a ’’figure-of-eight’’ shape. The electron diffraction patterns of SrMn 3 O 6show satellite reflections due to an mensurate modulation caused by the ordered Sr-distribution over