Abstract: | A redetermination of the structure of `La32.66Fe11S60' in the trigonal space group Rm led to the new formula La52Fe12S90 and to a redefinition of the structure type. In the structure, the Fe2+ cations occur in Fe2S9 dimers of face‐sharing octahedra (with 3m symmetry). The dimers are linked by face‐ and vertex‐sharing bi‐ and tricapped LaS6 trigonal prisms (with m symmetry) to form a three‐dimensional network containing two types of cuboctahedral cavities. The larger cavities remain empty, while the smaller ones accommodate alternative sites for disordered La3+ cations. |