Coordination preferences of the alkali cations sodium and caesium in the mixed-cationic Zintl ammoniate Cs_3.2Na_0.8Ge₉·5.3NH₃

The involvement of two different alkali cations in the nona­germanide ammoniate Cs_3.2Na_0.8Ge₉·5.3NH₃ provides insights into the coordination behaviour of ammonia towards Na and Cs cations within one compound and represents the first mixed-cationic solvate structure of nona­germanide tetra­anions.