The Solid Solutions M(19)Q(6)X(7) with M = Ag, Cu; Q = S, Se, Te and X = S, Se, Te

X-ray powder diffraction, EDX- and DSC measurements were performed in order to determine the structural and thermal properties of the solid solutions Ag19Te6Br7-xClx, Ag19Te6Br7-yIy, Ag19Te6-aSaBr7, Ag19Te6-bSebBr7 and Ag19-zCuzTe6Br7. Three different structure types, the Ag19Te6Br7, the Ag19Te5SeBr7 and the Ag19Te6Br5.4I1.6 type are realized, dependent on the type and grade of substitution. The Ag19Te6Br7 structure type is present for the solid solutions Ag19Te6Br7-xClx, Ag19Te6-aSaBr7 and Ag19-zCuzTe6Br7, For b >= 1 in case of Ag19Te6-bSebBr7 and for y >= 1.25 in Ag19Te6Br7-yIy the Ag19Te6Br7 structure type is replaced by Ag19Te5SeBr7 and the Ag19Te6Br5.4I1.6 structure type. All compounds show peritectic decomposition to the binary compounds Ag23Te12Br and Ag5Te2Cl, respectively.