K2Na4Co2O5 crystallizes in the monoclinic P2_1/c space group. K(1) is bonded in a 1-coordinate geometry to one O(3) and two equivalent O(1) atoms. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 5-coordinate geometry to one O(3), two equivalent O(1), and two equivalent O(2) atoms. In the second Na site, Na(2) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form distorted corner-sharing NaO4 trigonal pyramids. Co(1) is bonded in a distorted trigonal planar geometry to one O(1), one O(2), and one O(3) atom. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 7-coordinate geometry to two equivalent K(1), two equivalent Na(1), two equivalent Na(2), and one Co(1) atom. In the second O site, O(2) is bonded in a 5-coordinate geometry to two equivalent Na(1), two equivalent Na(2), and one Co(1) atom. In the third O site, O(3) is bonded in an octahedral geometry to two equivalent K(1), two equivalent Na(1), and two equivalent Co(1) atoms.
K2Na4Co2O5 crystallizes in the monoclinic P2_1/c space group. K(1) is bonded in a 1-coordinate geometry to one O(3) and two equivalent O(1) atoms. The K(1)-O(3) bond length is 2.75 Å. There is one shorter (3.01 Å) and one longer (3.23 Å) K(1)-O(1) bond length. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 5-coordinate geometry to one O(3), two equivalent O(1), and two equivalent O(2) atoms. The Na(1)-O(3) bond length is 2.31 Å. There is one shorter (2.28 Å) and one longer (2.64 Å) Na(1)-O(1) bond length. There is one shorter (2.30 Å) and one longer (2.67 Å) Na(1)-O(2) bond length. In the second Na site, Na(2) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form distorted corner-sharing NaO4 trigonal pyramids. There is one shorter (2.44 Å) and one longer (2.45 Å) Na(2)-O(1) bond length. Both Na(2)-O(2) bond lengths are 2.47 Å. Co(1) is bonded in a distorted trigonal planar geometry to one O(1), one O(2), and one O(3) atom. The Co(1)-O(1) bond length is 1.82 Å. The Co(1)-O(2) bond length is 1.82 Å. The Co(1)-O(3) bond length is 1.92 Å. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 7-coordinate geometry to two equivalent K(1), two equivalent Na(1), two equivalent Na(2), and one Co(1) atom. In the second O site, O(2) is bonded in a 5-coordinate geometry to two equivalent Na(1), two equivalent Na(2), and one Co(1) atom. In the third O site, O(3) is bonded in an octahedral geometry to two equivalent K(1), two equivalent Na(1), and two equivalent Co(1) atoms.