K2Na2MgLa2Nb2O10 crystallizes in the tetragonal P4mm space group. K(1) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(2), and four equivalent O(4) atoms. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 5-coordinate geometry to one O(1) and four equivalent O(4) atoms. In the second Na site, Na(2) is bonded in a distorted single-bond geometry to one O(2) and four equivalent O(3) atoms. Mg(1) is bonded in a 4-coordinate geometry to four equivalent O(3) atoms. La(1) is bonded in a body-centered cubic geometry to four equivalent O(3) and four equivalent O(4) atoms. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded in a distorted trigonal bipyramidal geometry to one O(1) and four equivalent O(3) atoms. In the second Nb site, Nb(2) is bonded in a distorted square pyramidal geometry to one O(2) and four equivalent O(4) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to four equivalent K(1), one Na(1), and one Nb(1) atom. In the second O site, O(2) is bonded to four equivalent K(1), one Na(2), and one Nb(2) atom to form distorted corner-sharing OK4NaNb octahedra. The corner-sharing octahedral tilt angles are 5°. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Na(2), one Mg(1), two equivalent La(1), and one Nb(1) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to two equivalent K(1), one Na(1), two equivalent La(1), and one Nb(2) atom.
K2Na2MgLa2Nb2O10 crystallizes in the tetragonal P4mm space group. K(1) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(2), and four equivalent O(4) atoms. Both K(1)-O(1) bond lengths are 3.10 Å. Both K(1)-O(2) bond lengths are 2.86 Å. All K(1)-O(4) bond lengths are 3.19 Å. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 5-coordinate geometry to one O(1) and four equivalent O(4) atoms. The Na(1)-O(1) bond length is 2.88 Å. All Na(1)-O(4) bond lengths are 2.23 Å. In the second Na site, Na(2) is bonded in a distorted single-bond geometry to one O(2) and four equivalent O(3) atoms. The Na(2)-O(2) bond length is 2.08 Å. All Na(2)-O(3) bond lengths are 2.75 Å. Mg(1) is bonded in a 4-coordinate geometry to four equivalent O(3) atoms. All Mg(1)-O(3) bond lengths are 2.19 Å. La(1) is bonded in a body-centered cubic geometry to four equivalent O(3) and four equivalent O(4) atoms. All La(1)-O(3) bond lengths are 2.66 Å. All La(1)-O(4) bond lengths are 2.52 Å. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded in a distorted trigonal bipyramidal geometry to one O(1) and four equivalent O(3) atoms. The Nb(1)-O(1) bond length is 1.88 Å. All Nb(1)-O(3) bond lengths are 2.03 Å. In the second Nb site, Nb(2) is bonded in a distorted square pyramidal geometry to one O(2) and four equivalent O(4) atoms. The Nb(2)-O(2) bond length is 1.97 Å. All Nb(2)-O(4) bond lengths are 1.99 Å. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to four equivalent K(1), one Na(1), and one Nb(1) atom. In the second O site, O(2) is bonded to four equivalent K(1), one Na(2), and one Nb(2) atom to form distorted corner-sharing OK4NaNb octahedra. The corner-sharing octahedral tilt angles are 5°. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Na(2), one Mg(1), two equivalent La(1), and one Nb(1) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to two equivalent K(1), one Na(1), two equivalent La(1), and one Nb(2) atom.