K3Na(CrO4)2 crystallizes in the monoclinic C2/c space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 1-coordinate geometry to one O(1) atom. In the second K site, K(2) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms. Na(1) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form NaO6 octahedra that share corners with six equivalent Cr(1)O4 tetrahedra. Cr(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form CrO4 tetrahedra that share corners with three equivalent Na(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 14-24°. There are four inequivalent O sites. In the first O site, O(3) is bonded in a 1-coordinate geometry to one K(2), one Na(1), and one Cr(1) atom. In the second O site, O(4) is bonded in a 2-coordinate geometry to one K(2), one Na(1), and one Cr(1) atom. In the third O site, O(1) is bonded in a 2-coordinate geometry to one K(1), one K(2), and one Cr(1) atom. In the fourth O site, O(2) is bonded in a 2-coordinate geometry to one K(2), one Na(1), and one Cr(1) atom.
K3Na(CrO4)2 crystallizes in the monoclinic C2/c space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 1-coordinate geometry to one O(1) atom. The K(1)-O(1) bond length is 2.60 Å. In the second K site, K(2) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms. Both K(2)-O(1) bond lengths are 3.29 Å. Both K(2)-O(2) bond lengths are 3.00 Å. Both K(2)-O(3) bond lengths are 2.93 Å. Both K(2)-O(4) bond lengths are 3.01 Å. Na(1) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form NaO6 octahedra that share corners with six equivalent Cr(1)O4 tetrahedra. Both Na(1)-O(2) bond lengths are 2.39 Å. Both Na(1)-O(3) bond lengths are 2.41 Å. Both Na(1)-O(4) bond lengths are 2.40 Å. Cr(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form CrO4 tetrahedra that share corners with three equivalent Na(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 14-24°. The Cr(1)-O(1) bond length is 1.64 Å. The Cr(1)-O(2) bond length is 1.68 Å. The Cr(1)-O(3) bond length is 1.67 Å. The Cr(1)-O(4) bond length is 1.67 Å. There are four inequivalent O sites. In the first O site, O(3) is bonded in a 1-coordinate geometry to one K(2), one Na(1), and one Cr(1) atom. In the second O site, O(4) is bonded in a 2-coordinate geometry to one K(2), one Na(1), and one Cr(1) atom. In the third O site, O(1) is bonded in a 2-coordinate geometry to one K(1), one K(2), and one Cr(1) atom. In the fourth O site, O(2) is bonded in a 2-coordinate geometry to one K(2), one Na(1), and one Cr(1) atom.