Synthèse et structure cristalline d'un matériau noir AgMnII3(MnIII0,26Al0,74)(MoO4)5

A new silver aluminium trimanganese pentamolybdate {silver(I) trimanganese(II) aluminium pentakis[tetraoxidomolybdate(VI)]}, AgMnII3(MnIII0,26Al0,74)(MoO4)5, has been synthesized using solid-state methods. The structure is composed of M2O10 dimers, M3O14 (M = Mn, Al) trimers and MoO4 tetrahedra sharing corners and forming three types of layers A, B and B′. The sequence of the constituting layers is A–BB′–A–BB′, with B′ obtained from B by inversion symmetry, forming a three-dimensional structure with large channels in which the positionally disordered and partially occupied Ag+ ions reside. The MnIII and AlIII atoms share the same site, M. AgMnII3(MnIII0,26Al0,74)(MoO4)5 is isotypic with the NaMg3X(MoO4)5 (X = Al, In) family and with NaFe4(MoO4)5. A comparative structural description is provided between the structure of the title compound and those of related phases containing dimers, trimers and tetramers.