Blue single crystals of K3Ag2Zr4F23 have been obtainend by heating up a mix
ture of KCL, Ag-powder and ZrOCl2 . 8H(2)O under with Ar diluted F-2 (T = 5
50 degrees C, t similar to 70 d). The compound crystallizes monoclinic, spa
ce group P2(1)/c-C-2h(5) (No.14) with a = 783,8(1)pm, b = 1117,4(2)pm, c =
1015,6(1)pm, beta = 97,45(1)degrees, Z = 2. The isotypic compound K3Ag2Hf4F
23, with a = 782,1(2) pm, b = 1115,4(2) pm, c = 1013,1(2) pm, beta = 97,51(
2)degrees, was prepared only as powder.