Cover illustration: The unit-cell packing of KMnAg3(CN)6, shown with 50% probability displacement ellipsoids. The coordination spheres of one Mn and one K atom are completed outside the unit cell for clarity, using broken bonds. The three interpenetrating networks are represented by the solid bonded strands (a,b,0) to (0,0,c), (a,b,0) to (0,0,0) to (0,b,c), and (a,0,0) to (a,b,c) to (0,b,0). See Geiser & Schlueter [Acta Cryst. (2003), C59, i21-i23].
The single-crystal structure of potassium manganese tris[dicyanoargentate(I)], KMnAg3(CN)6, is described. This is the first Mn-containing example of the triply interpenetrating MAg3(CN)6 type. The K+ ion is found to be located in an ordered manner on one of two possible interstitial sites, leading to a chiral space group.
Substitution of Cl by Br atoms into the known structure of SrCd2Cl6·8H2O leads to a disappearance of the twin phenomenon previously observed and a new arrangement of the Sr(H2O)9 polyhedra in chains by the sharing of bases of the triangular prisms.