Structural properties of image determined from high-resolution synchrotron powder diffraction

We report on the crystallographic structure of the layered compound Pb3Mn7O15Pb3Mn7O15. Previous analysis based on laboratory X-ray data at room temperature gave contradictory results in terms of the description of the unit cell. Motivated by recent magnetic bulk measurements of this system [N.V. Volkov, K.A. Sablina, O.A. Bayukov, E.V. Eremin, G.A. Petrakovskii, D.A. Velikanov, A.D. Balaev, A.F. Bovina, P. Boni, E. Clementyev, J. Phys. Condens. Matter 20 (2008) 055217], we re-investigated the chemical structure with high-resolution synchrotron powder diffraction at temperatures between 15 and 295 K. Our results show that the crystal structure of stoichiometric Pb3Mn7O15Pb3Mn7O15 has a pronounced 2-dimensional character and can be described in the orthorhombic space group Pnma.