K3Na(CrO4)2 crystallizes in the trigonal P-3m1 space group. There are two inequivalent K sites. In the first K site, K(1) is bonded to six equivalent O(1) atoms to form distorted KO6 cuboctahedra that share corners with six equivalent Cr(1)O4 tetrahedra and faces with two equivalent Na(1)O6 octahedra. In the second K site, K(2) is bonded in a 10-coordinate geometry to one O(2) and nine equivalent O(1) atoms. Na(1) is bonded to six equivalent O(1) atoms to form NaO6 octahedra that share corners with six equivalent Cr(1)O4 tetrahedra and faces with two equivalent K(1)O6 cuboctahedra. Cr(1) is bonded to one O(2) and three equivalent O(1) atoms to form CrO4 tetrahedra that share corners with three equivalent K(1)O6 cuboctahedra and corners with three equivalent Na(1)O6 octahedra. The corner-sharing octahedral tilt angles are 19°. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to one K(1), three equivalent K(2), one Na(1), and one Cr(1) atom. In the second O site, O(2) is bonded in a distorted linear geometry to one K(2) and one Cr(1) atom.
K3Na(CrO4)2 crystallizes in the trigonal P-3m1 space group. There are two inequivalent K sites. In the first K site, K(1) is bonded to six equivalent O(1) atoms to form distorted KO6 cuboctahedra that share corners with six equivalent Cr(1)O4 tetrahedra and faces with two equivalent Na(1)O6 octahedra. All K(1)-O(1) bond lengths are 2.88 Å. In the second K site, K(2) is bonded in a 10-coordinate geometry to one O(2) and nine equivalent O(1) atoms. The K(2)-O(2) bond length is 2.58 Å. There are six shorter (2.91 Å) and three longer (3.09 Å) K(2)-O(1) bond lengths. Na(1) is bonded to six equivalent O(1) atoms to form NaO6 octahedra that share corners with six equivalent Cr(1)O4 tetrahedra and faces with two equivalent K(1)O6 cuboctahedra. All Na(1)-O(1) bond lengths are 2.33 Å. Cr(1) is bonded to one O(2) and three equivalent O(1) atoms to form CrO4 tetrahedra that share corners with three equivalent K(1)O6 cuboctahedra and corners with three equivalent Na(1)O6 octahedra. The corner-sharing octahedral tilt angles are 19°. The Cr(1)-O(2) bond length is 1.62 Å. All Cr(1)-O(1) bond lengths are 1.65 Å. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to one K(1), three equivalent K(2), one Na(1), and one Cr(1) atom. In the second O site, O(2) is bonded in a distorted linear geometry to one K(2) and one Cr(1) atom.