Materials Data on KFe(MoO4)2 by Materials Project
KFe(MoO4)2 crystallizes in the trigonal P-3m1 space group. The structure is three-dimensional. K1+ is bonded to twelve O2- atoms to form KO12 cuboctahedra that share edges with six equivalent KO12 cuboctahedra, edges with six equivalent MoO4 tetrahedra, and faces with two equivalent FeO6 octahedra. There are six shorter (2.98 Å) and six longer (3.34 Å) K–O bond lengths. Mo6+ is bonded to four O2- atoms to form MoO4 tetrahedra that share corners with three equivalent FeO6 octahedra and edges with three equivalent KO12 cuboctahedra. The corner-sharing octahedral tilt angles are 19°. There is one shorter (1.75 Å) and three longer (1.81 Å) Mo–O bond length. Fe3+ is bonded to six equivalent O2- atoms to form FeO6 octahedra that share corners with six equivalent MoO4 tetrahedra and faces with two equivalent KO12 cuboctahedra. All Fe–O bond lengths are 2.01 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to three equivalent K1+ and one Mo6+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to one K1+, one Mo6+, and one Fe3+ atom.