K5Na3Ta6Nb2O24 is (Cubic) Perovskite-derived structured and crystallizes in the monoclinic Pm space group. There are five inequivalent K sites. In the first K site, K(1) is bonded to one O(1), one O(2), one O(3), one O(4), two equivalent O(10), two equivalent O(13), two equivalent O(15), and two equivalent O(9) atoms to form KO12 cuboctahedra that share corners with four equivalent K(4)O12 cuboctahedra, corners with four equivalent Na(2)O12 cuboctahedra, corners with four equivalent Na(3)O12 cuboctahedra, faces with two equivalent K(2)O12 cuboctahedra, faces with two equivalent K(3)O12 cuboctahedra, faces with two equivalent Na(1)O12 cuboctahedra, faces with two equivalent Ta(1)O6 octahedra, faces with two equivalent Ta(2)O6 octahedra, faces with two equivalent Ta(3)O6 octahedra, and faces with two equivalent Nb(1)O6 octahedra. In the second K site, K(2) is bonded to one O(1), one O(2), one O(3), one O(4), two equivalent O(11), two equivalent O(12), two equivalent O(13), and two equivalent O(15) atoms to form KO12 cuboctahedra that share corners with four equivalent K(3)O12 cuboctahedra, corners with four equivalent K(5)O12 cuboctahedra, corners with four equivalent Na(1)O12 cuboctahedra, faces with two equivalent K(1)O12 cuboctahedra, faces with two equivalent K(4)O12 cuboctahedra, faces with two equivalent Na(2)O12 cuboctahedra, faces with two equivalent Ta(1)O6 octahedra, faces with two equivalent Ta(2)O6 octahedra, faces with two equivalent Ta(3)O6 octahedra, and faces with two equivalent Nb(1)O6 octahedra. In the third K site, K(3) is bonded to one O(5), one O(6), one O(7), one O(8), two equivalent O(10), two equivalent O(13), two equivalent O(15), and two equivalent O(9) atoms to form KO12 cuboctahedra that share corners with four equivalent K(2)O12 cuboctahedra, corners with four equivalent K(5)O12 cuboctahedra, corners with four equivalent Na(1)O12 cuboctahedra, faces with two equivalent K(1)O12 cuboctahedra, faces with two equivalent K(4)O12 cuboctahedra, faces with two equivalent Na(3)O12 cuboctahedra, faces with two equivalent Ta(1)O6 octahedra, faces with two equivalent Ta(2)O6 octahedra, faces with two equivalent Ta(3)O6 octahedra, and faces with two equivalent Nb(1)O6 octahedra. In the fourth K site, K(4) is bonded to one O(5), one O(6), one O(7), one O(8), two equivalent O(11), two equivalent O(12), two equivalent O(13), and two equivalent O(15) atoms to form KO12 cuboctahedra that share corners with four equivalent K(1)O12 cuboctahedra, corners with four equivalent Na(2)O12 cuboctahedra, corners with four equivalent Na(3)O12 cuboctahedra, faces with two equivalent K(2)O12 cuboctahedra, faces with two equivalent K(3)O12 cuboctahedra, faces with two equivalent K(5)O12 cuboctahedra, faces with two equivalent Ta(1)O6 octahedra, faces with two equivalent Ta(2)O6 octahedra, faces with two equivalent Ta(3)O6 octahedra, and faces with two equivalent Nb(1)O6 octahedra. In the fifth K site, K(5) is bonded to one O(5), one O(6), one O(7), one O(8), two equivalent O(11), two equivalent O(12), two equivalent O(14), and two equivalent O(16) atoms to form KO12 cuboctahedra that share corners with four equivalent K(2)O12 cuboctahedra, corners with four equivalent K(3)O12 cuboctahedra, corners with four equivalent Na(1)O12 cuboctahedra, faces with two equivalent K(4)O12 cuboctahedra, faces with two equivalent Na(2)O12 cuboctahedra, faces with two equivalent Na(3)O12 cuboctahedra, faces with two equivalent Ta(1)O6 octahedra, faces with two equivalent Ta(2)O6 octahedra, faces with two equivalent Ta(3)O6 octahedra, and faces with two equivalent Nb(1)O6 octahedra. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded to one O(1), one O(2), one O(3), one O(4), two equivalent O(10), two equivalent O(14), two equivalent O(16), and two equivalent O(9) atoms to form NaO12 cuboctahedra that share corners with four equivalent K(2)O12 cuboctahedra, corners with four equivalent K(3)O12 cuboctahedra, corners with four equivalent K(5)O12 cuboctahedra, faces with two equivalent K(1)O12 cuboctahedra, faces with two equivalent Na(2)O12 cuboctahedra, faces with two equivalent Na(3)O12 cuboctahedra, faces with two equivalent Ta(1)O6 octahedra, faces with two equivalent Ta(2)O6 octahedra, faces with two equivalent Ta(3)O6 octahedra, and faces with two equivalent Nb(1)O6 octahedra. In the second Na site, Na(2) is bonded to one O(1), one O(2), one O(3), one O(4), two equivalent O(11), two equivalent O(12), two equivalent O(14), and two equivalent O(16) atoms to form NaO12 cuboctahedra that share corners with four equivalent K(1)O12 cuboctahedra, corners with four equivalent K(4)O12 cuboctahedra, corners with four equivalent Na(3)O12 cuboctahedra, faces with two equivalent K(2)O12 cuboctahedra, faces with two equivalent K(5)O12 cuboctahedra, faces with two equivalent Na(1)O12 cuboctahedra, faces with two equivalent Ta(1)O6 octahedra, faces with two equivalent Ta(2)O6 octahedra, faces with two equivalent Ta(3)O6 octahedra, and faces with two equivalent Nb(1)O6 octahedra. In the third Na site, Na(3) is bonded to one O(5), one O(6), one O(7), one O(8), two equivalent O(10), two equivalent O(14), two equivalent O(16), and two equivalent O(9) atoms to form NaO12 cuboctahedra that share corners with four equivalent K(1)O12 cuboctahedra, corners with four equivalent K(4)O12 cuboctahedra, corners with four equivalent Na(2)O12 cuboctahedra, faces with two equivalent K(3)O12 cuboctahedra, faces with two equivalent K(5)O12 cuboctahedra, faces with two equivalent Na(1)O12 cuboctahedra, faces with two equivalent Ta(1)O6 octahedra, faces with two equivalent Ta(2)O6 octahedra, faces with two equivalent Ta(3)O6 octahedra, and faces with two equivalent Nb(1)O6 octahedra. There are three inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to one O(1), one O(11), one O(13), one O(14), one O(5), and one O(9) atom to form TaO6 octahedra that share corners with two equivalent Ta(1)O6 octahedra, corners with two equivalent Ta(2)O6 octahedra, corners with two equivalent Ta(3)O6 octahedra,  a faceface with one K(1)O12 cuboctahedra,  a faceface with one K(2)O12 cuboctahedra,  a faceface with one K(3)O12 cuboctahedra,  a faceface with one K(4)O12 cuboctahedra,  a faceface with one K(5)O12 cuboctahedra,  a faceface with one Na(1)O12 cuboctahedra,  a faceface with one Na(2)O12 cuboctahedra, and  a faceface with one Na(3)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-1°. In the second Ta site, Ta(2) is bonded to one O(10), one O(12), one O(13), one O(14), one O(2), and one O(6) atom to form TaO6 octahedra that share corners with two equivalent Ta(1)O6 octahedra, corners with two equivalent Ta(2)O6 octahedra, corners with two equivalent Nb(1)O6 octahedra,  a faceface with one K(1)O12 cuboctahedra,  a faceface with one K(2)O12 cuboctahedra,  a faceface with one K(3)O12 cuboctahedra,  a faceface with one K(4)O12 cuboctahedra,  a faceface with one K(5)O12 cuboctahedra,  a faceface with one Na(1)O12 cuboctahedra,  a faceface with one Na(2)O12 cuboctahedra, and  a faceface with one Na(3)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-1°. In the third Ta site, Ta(3) is bonded to one O(11), one O(15), one O(16), one O(3), one O(7), and one O(9) atom to form TaO6 octahedra that share corners with two equivalent Ta(1)O6 octahedra, corners with two equivalent Ta(3)O6 octahedra, corners with two equivalent Nb(1)O6 octahedra,  a faceface with one K(1)O12 cuboctahedra,  a faceface with one K(2)O12 cuboctahedra,  a faceface with one K(3)O12 cuboctahedra,  a faceface with one K(4)O12 cuboctahedra,  a faceface with one K(5)O12 cuboctahedra,  a faceface with one Na(1)O12 cuboctahedra,  a faceface with one Na(2)O12 cuboctahedra, and  a faceface with one Na(3)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-1°. Nb(1) is bonded to one O(10), one O(12), one O(15), one O(16), one O(4), and one O(8) atom to form NbO6 octahedra that share corners with two equivalent Ta(2)O6 octahedra, corners with two equivalent Ta(3)O6 octahedra, corners with two equivalent Nb(1)O6 octahedra,  a faceface with one K(1)O12 cuboctahedra,  a faceface with one K(2)O12 cuboctahedra,  a faceface with one K(3)O12 cuboctahedra,  a faceface with one K(4)O12 cuboctahedra,  a faceface with one K(5)O12 cuboctahedra,  a faceface with one Na(1)O12 cuboctahedra,  a faceface with one Na(2)O12 cuboctahedra, and  a faceface with one Na(3)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-1°. There are sixteen inequivalent O sites. In the first O site, O(1) is bonded in a distorted linear geometry to one K(1), one K(2), one Na(1), one Na(2), and two equivalent Ta(1) atoms. In the second O site, O(2) is bonded in a distorted linear geometry to one K(1), one K(2), one Na(1), one Na(2), and two equivalent Ta(2) atoms. In the third O site, O(3) is bonded in a distorted linear geometry to one K(1), one K(2), one Na(1), one Na(2), and two equivalent Ta(3) atoms. In the fourth O site, O(4) is bonded in a distorted linear geometry to one K(1), one K(2), one Na(1), one Na(2), and two equivalent Nb(1) atoms. In the fifth O site, O(5) is bonded in a distorted linear geometry to one K(3), one K(4), one K(5), one Na(3), and two equivalent Ta(1) atoms. In the sixth O site, O(6) is bonded in a distorted linear geometry to one K(3), one K(4), one K(5), one Na(3), and two equivalent Ta(2) atoms. In the seventh O site, O(7) is bonded in a distorted linear geometry to one K(3), one K(4), one K(5), one Na(3), and two equivalent Ta(3) atoms. In the eighth O site, O(8) is bonded in a distorted linear geometry to one K(3), one K(4), one K(5), one Na(3), and two equivalent Nb(1) atoms. In the ninth O site, O(9) is bonded in a distorted linear geometry to one K(1), one K(3), one Na(1), one Na(3), one Ta(1), and one Ta(3) atom. In the tenth O site, O(10) is bonded in a distorted linear geometry to one K(1), one K(3), one Na(1), one Na(3), one Ta(2), and one Nb(1) atom. In the eleventh O site, O(11) is bonded in a distorted linear geometry to one K(2), one K(4), one K(5), one Na(2), one Ta(1), and one Ta(3) atom. In the twelfth O site, O(12) is bonded in a distorted linear geometry to one K(2), one K(4), one K(5), one Na(2), one Ta(2), and one Nb(1) atom. In the thirteenth O site, O(13) is bonded in a distorted linear geometry to one K(1), one K(2), one K(3), one K(4), one Ta(1), and one Ta(2) atom. In the fourteenth O site, O(14) is bonded in a distorted linear geometry to one K(5), one Na(1), one Na(2), one Na(3), one Ta(1), and one Ta(2) atom. In the fifteenth O site, O(15) is bonded in a distorted linear geometry to one K(1), one K(2), one K(3), one K(4), one Ta(3), and one Nb(1) atom. In the sixteenth O site, O(16) is bonded in a distorted linear geometry to one K(5), one Na(1), one Na(2), one Na(3), one Ta(3), and one Nb(1) atom.
K5Na3Ta6Nb2O24 is (Cubic) Perovskite-derived structured and crystallizes in the monoclinic Pm space group. There are five inequivalent K sites. In the first K site, K(1) is bonded to one O(1), one O(2), one O(3), one O(4), two equivalent O(10), two equivalent O(13), two equivalent O(15), and two equivalent O(9) atoms to form KO12 cuboctahedra that share corners with four equivalent K(4)O12 cuboctahedra, corners with four equivalent Na(2)O12 cuboctahedra, corners with four equivalent Na(3)O12 cuboctahedra, faces with two equivalent K(2)O12 cuboctahedra, faces with two equivalent K(3)O12 cuboctahedra, faces with two equivalent Na(1)O12 cuboctahedra, faces with two equivalent Ta(1)O6 octahedra, faces with two equivalent Ta(2)O6 octahedra, faces with two equivalent Ta(3)O6 octahedra, and faces with two equivalent Nb(1)O6 octahedra. The K(1)-O(1) bond length is 2.86 Å. The K(1)-O(2) bond length is 2.86 Å. The K(1)-O(3) bond length is 2.86 Å. The K(1)-O(4) bond length is 2.85 Å. Both K(1)-O(10) bond lengths are 2.86 Å. Both K(1)-O(13) bond lengths are 2.84 Å. Both K(1)-O(15) bond lengths are 2.84 Å. Both K(1)-O(9) bond lengths are 2.86 Å. In the second K site, K(2) is bonded to one O(1), one O(2), one O(3), one O(4), two equivalent O(11), two equivalent O(12), two equivalent O(13), and two equivalent O(15) atoms to form KO12 cuboctahedra that share corners with four equivalent K(3)O12 cuboctahedra, corners with four equivalent K(5)O12 cuboctahedra, corners with four equivalent Na(1)O12 cuboctahedra, faces with two equivalent K(1)O12 cuboctahedra, faces with two equivalent K(4)O12 cuboctahedra, faces with two equivalent Na(2)O12 cuboctahedra, faces with two equivalent Ta(1)O6 octahedra, faces with two equivalent Ta(2)O6 octahedra, faces with two equivalent Ta(3)O6 octahedra, and faces with two equivalent Nb(1)O6 octahedra. The K(2)-O(1) bond length is 2.86 Å. The K(2)-O(2) bond length is 2.86 Å. The K(2)-O(3) bond length is 2.86 Å. The K(2)-O(4) bond length is 2.86 Å. Both K(2)-O(11) bond lengths are 2.85 Å. Both K(2)-O(12) bond lengths are 2.85 Å. Both K(2)-O(13) bond lengths are 2.85 Å. Both K(2)-O(15) bond lengths are 2.85 Å. In the third K site, K(3) is bonded to one O(5), one O(6), one O(7), one O(8), two equivalent O(10), two equivalent O(13), two equivalent O(15), and two equivalent O(9) atoms to form KO12 cuboctahedra that share corners with four equivalent K(2)O12 cuboctahedra, corners with four equivalent K(5)O12 cuboctahedra, corners with four equivalent Na(1)O12 cuboctahedra, faces with two equivalent K(1)O12 cuboctahedra, faces with two equivalent K(4)O12 cuboctahedra, faces with two equivalent Na(3)O12 cuboctahedra, faces with two equivalent Ta(1)O6 octahedra, faces with two equivalent Ta(2)O6 octahedra, faces with two equivalent Ta(3)O6 octahedra, and faces with two equivalent Nb(1)O6 octahedra. The K(3)-O(5) bond length is 2.85 Å. The K(3)-O(6) bond length is 2.85 Å. The K(3)-O(7) bond length is 2.85 Å. The K(3)-O(8) bond length is 2.85 Å. Both K(3)-O(10) bond lengths are 2.86 Å. Both K(3)-O(13) bond lengths are 2.85 Å. Both K(3)-O(15) bond lengths are 2.85 Å. Both K(3)-O(9) bond lengths are 2.86 Å. In the fourth K site, K(4) is bonded to one O(5), one O(6), one O(7), one O(8), two equivalent O(11), two equivalent O(12), two equivalent O(13), and two equivalent O(15) atoms to form KO12 cuboctahedra that share corners with four equivalent K(1)O12 cuboctahedra, corners with four equivalent Na(2)O12 cuboctahedra, corners with four equivalent Na(3)O12 cuboctahedra, faces with two equivalent K(2)O12 cuboctahedra, faces with two equivalent K(3)O12 cuboctahedra, faces with two equivalent K(5)O12 cuboctahedra, faces with two equivalent Ta(1)O6 octahedra, faces with two equivalent Ta(2)O6 octahedra, faces with two equivalent Ta(3)O6 octahedra, and faces with two equivalent Nb(1)O6 octahedra. The K(4)-O(5) bond length is 2.86 Å. The K(4)-O(6) bond length is 2.86 Å. The K(4)-O(7) bond length is 2.86 Å. The K(4)-O(8) bond length is 2.86 Å. Both K(4)-O(11) bond lengths are 2.86 Å. Both K(4)-O(12) bond lengths are 2.86 Å. Both K(4)-O(13) bond lengths are 2.85 Å. Both K(4)-O(15) bond lengths are 2.85 Å. In the fifth K site, K(5) is bonded to one O(5), one O(6), one O(7), one O(8), two equivalent O(11), two equivalent O(12), two equivalent O(14), and two equivalent O(16) atoms to form KO12 cuboctahedra that share corners with four equivalent K(2)O12 cuboctahedra, corners with four equivalent K(3)O12 cuboctahedra, corners with four equivalent Na(1)O12 cuboctahedra, faces with two equivalent K(4)O12 cuboctahedra, faces with two equivalent Na(2)O12 cuboctahedra, faces with two equivalent Na(3)O12 cuboctahedra, faces with two equivalent Ta(1)O6 octahedra, faces with two equivalent Ta(2)O6 octahedra, faces with two equivalent Ta(3)O6 octahedra, and faces with two equivalent Nb(1)O6 octahedra. The K(5)-O(5) bond length is 2.85 Å. The K(5)-O(6) bond length is 2.84 Å. The K(5)-O(7) bond length is 2.84 Å. The K(5)-O(8) bond length is 2.84 Å. Both K(5)-O(11) bond lengths are 2.84 Å. Both K(5)-O(12) bond lengths are 2.84 Å. Both K(5)-O(14) bond lengths are 2.86 Å. Both K(5)-O(16) bond lengths are 2.86 Å. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded to one O(1), one O(2), one O(3), one O(4), two equivalent O(10), two equivalent O(14), two equivalent O(16), and two equivalent O(9) atoms to form NaO12 cuboctahedra that share corners with four equivalent K(2)O12 cuboctahedra, corners with four equivalent K(3)O12 cuboctahedra, corners with four equivalent K(5)O12 cuboctahedra, faces with two equivalent K(1)O12 cuboctahedra, faces with two equivalent Na(2)O12 cuboctahedra, faces with two equivalent Na(3)O12 cuboctahedra, faces with two equivalent Ta(1)O6 octahedra, faces with two equivalent Ta(2)O6 octahedra, faces with two equivalent Ta(3)O6 octahedra, and faces with two equivalent Nb(1)O6 octahedra. The Na(1)-O(1) bond length is 2.83 Å. The Na(1)-O(2) bond length is 2.83 Å. The Na(1)-O(3) bond length is 2.83 Å. The Na(1)-O(4) bond length is 2.83 Å. Both Na(1)-O(10) bond lengths are 2.83 Å. Both Na(1)-O(14) bond lengths are 2.84 Å. Both Na(1)-O(16) bond lengths are 2.84 Å. Both Na(1)-O(9) bond lengths are 2.83 Å. In the second Na site, Na(2) is bonded to one O(1), one O(2), one O(3), one O(4), two equivalent O(11), two equivalent O(12), two equivalent O(14), and two equivalent O(16) atoms to form NaO12 cuboctahedra that share corners with four equivalent K(1)O12 cuboctahedra, corners with four equivalent K(4)O12 cuboctahedra, corners with four equivalent Na(3)O12 cuboctahedra, faces with two equivalent K(2)O12 cuboctahedra, faces with two equivalent K(5)O12 cuboctahedra, faces with two equivalent Na(1)O12 cuboctahedra, faces with two equivalent Ta(1)O6 octahedra, faces with two equivalent Ta(2)O6 octahedra, faces with two equivalent Ta(3)O6 octahedra, and faces with two equivalent Nb(1)O6 octahedra. The Na(2)-O(1) bond length is 2.84 Å. The Na(2)-O(2) bond length is 2.84 Å. The Na(2)-O(3) bond length is 2.84 Å. The Na(2)-O(4) bond length is 2.84 Å. Both Na(2)-O(11) bond lengths are 2.83 Å. Both Na(2)-O(12) bond lengths are 2.83 Å. Both Na(2)-O(14) bond lengths are 2.85 Å. Both Na(2)-O(16) bond lengths are 2.85 Å. In the third Na site, Na(3) is bonded to one O(5), one O(6), one O(7), one O(8), two equivalent O(10), two equivalent O(14), two equivalent O(16), and two equivalent O(9) atoms to form NaO12 cuboctahedra that share corners with four equivalent K(1)O12 cuboctahedra, corners with four equivalent K(4)O12 cuboctahedra, corners with four equivalent Na(2)O12 cuboctahedra, faces with two equivalent K(3)O12 cuboctahedra, faces with two equivalent K(5)O12 cuboctahedra, faces with two equivalent Na(1)O12 cuboctahedra, faces with two equivalent Ta(1)O6 octahedra, faces with two equivalent Ta(2)O6 octahedra, faces with two equivalent Ta(3)O6 octahedra, and faces with two equivalent Nb(1)O6 octahedra. The Na(3)-O(5) bond length is 2.83 Å. The Na(3)-O(6) bond length is 2.83 Å. The Na(3)-O(7) bond length is 2.83 Å. The Na(3)-O(8) bond length is 2.83 Å. Both Na(3)-O(10) bond lengths are 2.84 Å. Both Na(3)-O(14) bond lengths are 2.85 Å. Both Na(3)-O(16) bond lengths are 2.85 Å. Both Na(3)-O(9) bond lengths are 2.84 Å. There are three inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to one O(1), one O(11), one O(13), one O(14), one O(5), and one O(9) atom to form TaO6 octahedra that share corners with two equivalent Ta(1)O6 octahedra, corners with two equivalent Ta(2)O6 octahedra, corners with two equivalent Ta(3)O6 octahedra,  a faceface with one K(1)O12 cuboctahedra,  a faceface with one K(2)O12 cuboctahedra,  a faceface with one K(3)O12 cuboctahedra,  a faceface with one K(4)O12 cuboctahedra,  a faceface with one K(5)O12 cuboctahedra,  a faceface with one Na(1)O12 cuboctahedra,  a faceface with one Na(2)O12 cuboctahedra, and  a faceface with one Na(3)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-1°. The Ta(1)-O(1) bond length is 2.01 Å. The Ta(1)-O(11) bond length is 2.01 Å. The Ta(1)-O(13) bond length is 2.02 Å. The Ta(1)-O(14) bond length is 2.01 Å. The Ta(1)-O(5) bond length is 2.01 Å. The Ta(1)-O(9) bond length is 2.01 Å. In the second Ta site, Ta(2) is bonded to one O(10), one O(12), one O(13), one O(14), one O(2), and one O(6) atom to form TaO6 octahedra that share corners with two equivalent Ta(1)O6 octahedra, corners with two equivalent Ta(2)O6 octahedra, corners with two equivalent Nb(1)O6 octahedra,  a faceface with one K(1)O12 cuboctahedra,  a faceface with one K(2)O12 cuboctahedra,  a faceface with one K(3)O12 cuboctahedra,  a faceface with one K(4)O12 cuboctahedra,  a faceface with one K(5)O12 cuboctahedra,  a faceface with one Na(1)O12 cuboctahedra,  a faceface with one Na(2)O12 cuboctahedra, and  a faceface with one Na(3)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-1°. The Ta(2)-O(10) bond length is 2.00 Å. The Ta(2)-O(12) bond length is 2.00 Å. The Ta(2)-O(13) bond length is 2.02 Å. The Ta(2)-O(14) bond length is 2.01 Å. The Ta(2)-O(2) bond length is 2.01 Å. The Ta(2)-O(6) bond length is 2.01 Å. In the third Ta site, Ta(3) is bonded to one O(11), one O(15), one O(16), one O(3), one O(7), and one O(9) atom to form TaO6 octahedra that share corners with two equivalent Ta(1)O6 octahedra, corners with two equivalent Ta(3)O6 octahedra, corners with two equivalent Nb(1)O6 octahedra,  a faceface with one K(1)O12 cuboctahedra,  a faceface with one K(2)O12 cuboctahedra,  a faceface with one K(3)O12 cuboctahedra,  a faceface with one K(4)O12 cuboctahedra,  a faceface with one K(5)O12 cuboctahedra,  a faceface with one Na(1)O12 cuboctahedra,  a faceface with one Na(2)O12 cuboctahedra, and  a faceface with one Na(3)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-1°. The Ta(3)-O(11) bond length is 2.02 Å. The Ta(3)-O(15) bond length is 2.01 Å. The Ta(3)-O(16) bond length is 2.00 Å. The Ta(3)-O(3) bond length is 2.01 Å. The Ta(3)-O(7) bond length is 2.01 Å. The Ta(3)-O(9) bond length is 2.01 Å. Nb(1) is bonded to one O(10), one O(12), one O(15), one O(16), one O(4), and one O(8) atom to form NbO6 octahedra that share corners with two equivalent Ta(2)O6 octahedra, corners with two equivalent Ta(3)O6 octahedra, corners with two equivalent Nb(1)O6 octahedra,  a faceface with one K(1)O12 cuboctahedra,  a faceface with one K(2)O12 cuboctahedra,  a faceface with one K(3)O12 cuboctahedra,  a faceface with one K(4)O12 cuboctahedra,  a faceface with one K(5)O12 cuboctahedra,  a faceface with one Na(1)O12 cuboctahedra,  a faceface with one Na(2)O12 cuboctahedra, and  a faceface with one Na(3)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-1°. The Nb(1)-O(10) bond length is 2.02 Å. The Nb(1)-O(12) bond length is 2.02 Å. The Nb(1)-O(15) bond length is 2.03 Å. The Nb(1)-O(16) bond length is 2.02 Å. The Nb(1)-O(4) bond length is 2.01 Å. The Nb(1)-O(8) bond length is 2.01 Å. There are sixteen inequivalent O sites. In the first O site, O(1) is bonded in a distorted linear geometry to one K(1), one K(2), one Na(1), one Na(2), and two equivalent Ta(1) atoms. In the second O site, O(2) is bonded in a distorted linear geometry to one K(1), one K(2), one Na(1), one Na(2), and two equivalent Ta(2) atoms. In the third O site, O(3) is bonded in a distorted linear geometry to one K(1), one K(2), one Na(1), one Na(2), and two equivalent Ta(3) atoms. In the fourth O site, O(4) is bonded in a distorted linear geometry to one K(1), one K(2), one Na(1), one Na(2), and two equivalent Nb(1) atoms. In the fifth O site, O(5) is bonded in a distorted linear geometry to one K(3), one K(4), one K(5), one Na(3), and two equivalent Ta(1) atoms. In the sixth O site, O(6) is bonded in a distorted linear geometry to one K(3), one K(4), one K(5), one Na(3), and two equivalent Ta(2) atoms. In the seventh O site, O(7) is bonded in a distorted linear geometry to one K(3), one K(4), one K(5), one Na(3), and two equivalent Ta(3) atoms. In the eighth O site, O(8) is bonded in a distorted linear geometry to one K(3), one K(4), one K(5), one Na(3), and two equivalent Nb(1) atoms. In the ninth O site, O(9) is bonded in a distorted linear geometry to one K(1), one K(3), one Na(1), one Na(3), one Ta(1), and one Ta(3) atom. In the tenth O site, O(10) is bonded in a distorted linear geometry to one K(1), one K(3), one Na(1), one Na(3), one Ta(2), and one Nb(1) atom. In the eleventh O site, O(11) is bonded in a distorted linear geometry to one K(2), one K(4), one K(5), one Na(2), one Ta(1), and one Ta(3) atom. In the twelfth O site, O(12) is bonded in a distorted linear geometry to one K(2), one K(4), one K(5), one Na(2), one Ta(2), and one Nb(1) atom. In the thirteenth O site, O(13) is bonded in a distorted linear geometry to one K(1), one K(2), one K(3), one K(4), one Ta(1), and one Ta(2) atom. In the fourteenth O site, O(14) is bonded in a distorted linear geometry to one K(5), one Na(1), one Na(2), one Na(3), one Ta(1), and one Ta(2) atom. In the fifteenth O site, O(15) is bonded in a distorted linear geometry to one K(1), one K(2), one K(3), one K(4), one Ta(3), and one Nb(1) atom. In the sixteenth O site, O(16) is bonded in a distorted linear geometry to one K(5), one Na(1), one Na(2), one Na(3), one Ta(3), and one Nb(1) atom.