Synthesis and structures of type-I clathrates: Rb6Na2Ge44.89(1), Cs6Na2Zn4Ge42 and Cs6.40(1)Na1.60(1)Ga8Ge38

The Intermetallic Type‐I Clathrate Na8Zn4Ge42

“…Another type‐I clathrate with Tt = Ge and T = Zn (besides K 8 Zn x Ge 46– x mentioned above) is Ba 8 Zn 8 Ge 38 . Na atoms in guest positions are less frequent but are found in Rb 6 Na 2 Ge 44.89 , Cs 6 Na 2 Zn 4 Ge 42 and Cs 6.40 Na 1.60 Ga 8 Ge 38 , as well as in Na 8 Tr x Ge 46– x with Tr = Al and Ga . Notably, a binary A 8 Ge 46– y □ y phase with A = Na has not been reported, and Na is generally considered not to fit well in the larger cages of a Ge type‐I clathrate host framework .…”