Synthèse et structure cristalline d’un matériau noir AgMnII 3(MnIII 0,26Al0,74)(MoO4)5

A new silver aluminium trimangan­ese penta­molybdate, AgMn II 3 (Mn III 0,26 Al 0,74 )(MoO 4 ) 5 , is composed of M 2 O 10 dimers, M 3 O 14 ( M = Mn, Al) trimers and MoO 4 tetra­hedra sharing corners and forming three types of layers. A comparative structural description is provided with the structures of related phases containing dimers, trimers and tetra­mers. A new silver aluminium trimangan­ese penta­molybdate {silver(I) trimanganese(II) aluminium penta­kis­[tetra­oxidomolybdate(VI)]}, AgMn II 3 (Mn III 0,26 Al 0,74 )(MoO 4 ) 5 , has been synthesized using solid-state methods. The structure is composed of M 2 O 10 dimers, M 3 O 14 ( M = Mn, Al) trimers and MoO 4 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 Mn III and Al III atoms share the same site, M . AgMn II 3 (Mn III 0,26 Al 0,74 )(MoO 4 ) 5 is isotypic with the NaMg 3 X (MoO 4 ) 5 ( X = Al, In) family and with NaFe 4 (MoO 4 ) 5 . A comparative structural description is provided between the structure of the title compound and those of related phases containing dimers, trimers and tetra­mers.