KFe(SO4)2 crystallizes in the triclinic P-1 space group. K(1) is bonded in a 10-coordinate geometry to two equivalent O(1), two equivalent O(2), and six equivalent O(4) atoms. Fe(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form FeO6 octahedra that share corners with six equivalent S(1)O4 tetrahedra. S(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form SO4 tetrahedra that share corners with three equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 37-47°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to one K(1), one Fe(1), and one S(1) atom. In the second O site, O(2) is bonded in a 2-coordinate geometry to one K(1), one Fe(1), and one S(1) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Fe(1) and one S(1) atom. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to three equivalent K(1) and one S(1) atom.
KFe(SO4)2 crystallizes in the triclinic P-1 space group. K(1) is bonded in a 10-coordinate geometry to two equivalent O(1), two equivalent O(2), and six equivalent O(4) atoms. Both K(1)-O(1) bond lengths are 2.94 Å. Both K(1)-O(2) bond lengths are 2.86 Å. There are a spread of K(1)-O(4) bond distances ranging from 2.84-3.17 Å. Fe(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form FeO6 octahedra that share corners with six equivalent S(1)O4 tetrahedra. Both Fe(1)-O(1) bond lengths are 2.02 Å. Both Fe(1)-O(2) bond lengths are 1.95 Å. Both Fe(1)-O(3) bond lengths are 1.95 Å. S(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form SO4 tetrahedra that share corners with three equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 37-47°. The S(1)-O(1) bond length is 1.50 Å. The S(1)-O(2) bond length is 1.52 Å. The S(1)-O(3) bond length is 1.48 Å. The S(1)-O(4) bond length is 1.46 Å. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to one K(1), one Fe(1), and one S(1) atom. In the second O site, O(2) is bonded in a 2-coordinate geometry to one K(1), one Fe(1), and one S(1) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Fe(1) and one S(1) atom. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to three equivalent K(1) and one S(1) atom.