NEUTRON POWDER DIFFRACTION STUDY OF THE CRYSTAL-STRUCTURE OF THE LAYERED MINERAL KRAUTITE, DMNASO4.D2O

The crystal structure of a deuterium-substituted analogue of the layer ed mineral krautite, DMnAsO4.D2O, has been determined at room temperat ure by high resolution neutron powder diffraction with special referen ce to the D-atom positions. The compound crystallises in a monoclinic space group P2(1) with a = 8.00860(4), b = 15.94783(9), c = 6.82015(4) Angstrom, beta = 96.608(2)degrees; 2=2, R(p) = 4.9%, R(wp) = 1.6%. Th e AsO4 and MnO6 coordination polyhedra are connected by sharing edges and vertices to form (010) layers linked by hydrogen-bonds. None of th e hydrogen-bonds is of bifurcated type.