Na4FeO5 crystallizes in the triclinic P1 space group. There are sixteen inequivalent Na sites. In the first Na site, Na(1) is bonded to one O(1), one O(13), one O(19), one O(9), and two equivalent O(5) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Na(11)O6 octahedra,  a cornercorner with one Na(13)O6 octahedra,  a cornercorner with one Na(7)O6 octahedra, corners with two equivalent Na(1)O6 octahedra,  a cornercorner with one Fe(2)O5 square pyramid,  a cornercorner with one Fe(3)O5 square pyramid,  an edgeedge with one Na(12)O6 octahedra,  an edgeedge with one Na(13)O6 octahedra,  an edgeedge with one Na(7)O6 octahedra, edges with two equivalent Na(15)O6 octahedra, edges with two equivalent Na(5)O6 octahedra, edges with two equivalent Na(9)O6 octahedra,  an edgeedge with one Fe(3)O5 square pyramid, and  an edgeedge with one Fe(4)O5 square pyramid. The corner-sharing octahedral tilt angles range from 20-24°. In the second Na site, Na(2) is bonded to one O(10), one O(14), one O(2), one O(20), and two equivalent O(6) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Na(12)O6 octahedra,  a cornercorner with one Na(14)O6 octahedra,  a cornercorner with one Na(8)O6 octahedra, corners with two equivalent Na(2)O6 octahedra,  a cornercorner with one Fe(1)O5 square pyramid,  a cornercorner with one Fe(4)O5 square pyramid,  an edgeedge with one Na(11)O6 octahedra,  an edgeedge with one Na(14)O6 octahedra,  an edgeedge with one Na(8)O6 octahedra, edges with two equivalent Na(10)O6 octahedra, edges with two equivalent Na(16)O6 octahedra, edges with two equivalent Na(6)O6 octahedra,  an edgeedge with one Fe(1)O5 square pyramid, and  an edgeedge with one Fe(2)O5 square pyramid. The corner-sharing octahedral tilt angles range from 20-24°. In the third Na site, Na(3) is bonded to one O(11), one O(15), one O(18), one O(3), and two equivalent O(7) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Na(10)O6 octahedra,  a cornercorner with one Na(15)O6 octahedra,  a cornercorner with one Na(6)O6 octahedra, corners with two equivalent Na(3)O6 octahedra,  a cornercorner with one Fe(3)O5 square pyramid,  a cornercorner with one Fe(4)O5 square pyramid,  an edgeedge with one Na(15)O6 octahedra,  an edgeedge with one Na(6)O6 octahedra,  an edgeedge with one Na(9)O6 octahedra, edges with two equivalent Na(11)O6 octahedra, edges with two equivalent Na(14)O6 octahedra, edges with two equivalent Na(7)O6 octahedra,  an edgeedge with one Fe(1)O5 square pyramid, and  an edgeedge with one Fe(4)O5 square pyramid. The corner-sharing octahedral tilt angles range from 20-25°. In the fourth Na site, Na(4) is bonded to one O(12), one O(16), one O(17), one O(4), and two equivalent O(8) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Na(16)O6 octahedra,  a cornercorner with one Na(5)O6 octahedra,  a cornercorner with one Na(9)O6 octahedra, corners with two equivalent Na(4)O6 octahedra,  a cornercorner with one Fe(1)O5 square pyramid,  a cornercorner with one Fe(2)O5 square pyramid,  an edgeedge with one Na(10)O6 octahedra,  an edgeedge with one Na(16)O6 octahedra,  an edgeedge with one Na(5)O6 octahedra, edges with two equivalent Na(12)O6 octahedra, edges with two equivalent Na(13)O6 octahedra, edges with two equivalent Na(8)O6 octahedra,  an edgeedge with one Fe(2)O5 square pyramid, and  an edgeedge with one Fe(3)O5 square pyramid. The corner-sharing octahedral tilt angles range from 20-25°. In the fifth Na site, Na(5) is bonded to one O(16), one O(17), one O(4), one O(5), and two equivalent O(9) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Na(10)O6 octahedra,  a cornercorner with one Na(15)O6 octahedra,  a cornercorner with one Na(4)O6 octahedra, corners with two equivalent Na(5)O6 octahedra,  a cornercorner with one Fe(2)O5 square pyramid,  a cornercorner with one Fe(3)O5 square pyramid,  an edgeedge with one Na(16)O6 octahedra,  an edgeedge with one Na(4)O6 octahedra,  an edgeedge with one Na(9)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, edges with two equivalent Na(12)O6 octahedra, edges with two equivalent Na(13)O6 octahedra,  an edgeedge with one Fe(2)O5 square pyramid, and  an edgeedge with one Fe(3)O5 square pyramid. The corner-sharing octahedral tilt angles range from 20-25°. In the sixth Na site, Na(6) is bonded to one O(15), one O(18), one O(3), one O(6), and two equivalent O(10) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Na(16)O6 octahedra,  a cornercorner with one Na(3)O6 octahedra,  a cornercorner with one Na(9)O6 octahedra, corners with two equivalent Na(6)O6 octahedra,  a cornercorner with one Fe(1)O5 square pyramid,  a cornercorner with one Fe(4)O5 square pyramid,  an edgeedge with one Na(10)O6 octahedra,  an edgeedge with one Na(15)O6 octahedra,  an edgeedge with one Na(3)O6 octahedra, edges with two equivalent Na(11)O6 octahedra, edges with two equivalent Na(14)O6 octahedra, edges with two equivalent Na(2)O6 octahedra,  an edgeedge with one Fe(1)O5 square pyramid, and  an edgeedge with one Fe(4)O5 square pyramid. The corner-sharing octahedral tilt angles range from 20-25°. In the seventh Na site, Na(7) is bonded to one O(1), one O(13), one O(19), one O(7), and two equivalent O(11) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Na(1)O6 octahedra,  a cornercorner with one Na(12)O6 octahedra,  a cornercorner with one Na(14)O6 octahedra, corners with two equivalent Na(7)O6 octahedra,  a cornercorner with one Fe(3)O5 square pyramid,  a cornercorner with one Fe(4)O5 square pyramid,  an edgeedge with one Na(1)O6 octahedra,  an edgeedge with one Na(11)O6 octahedra,  an edgeedge with one Na(13)O6 octahedra, edges with two equivalent Na(15)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, edges with two equivalent Na(9)O6 octahedra,  an edgeedge with one Fe(3)O5 square pyramid, and  an edgeedge with one Fe(4)O5 square pyramid. The corner-sharing octahedral tilt angles range from 20-24°. In the eighth Na site, Na(8) is bonded to one O(14), one O(2), one O(20), one O(8), and two equivalent O(12) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Na(11)O6 octahedra,  a cornercorner with one Na(13)O6 octahedra,  a cornercorner with one Na(2)O6 octahedra, corners with two equivalent Na(8)O6 octahedra,  a cornercorner with one Fe(1)O5 square pyramid,  a cornercorner with one Fe(2)O5 square pyramid,  an edgeedge with one Na(12)O6 octahedra,  an edgeedge with one Na(14)O6 octahedra,  an edgeedge with one Na(2)O6 octahedra, edges with two equivalent Na(10)O6 octahedra, edges with two equivalent Na(16)O6 octahedra, edges with two equivalent Na(4)O6 octahedra,  an edgeedge with one Fe(1)O5 square pyramid, and  an edgeedge with one Fe(2)O5 square pyramid. The corner-sharing octahedral tilt angles range from 20-24°. In the ninth Na site, Na(9) is bonded to one O(11), one O(17), one O(3), one O(5), and two equivalent O(13) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Na(15)O6 octahedra,  a cornercorner with one Na(4)O6 octahedra,  a cornercorner with one Na(6)O6 octahedra, corners with two equivalent Na(9)O6 octahedra,  a cornercorner with one Fe(3)O5 square pyramid,  a cornercorner with one Fe(4)O5 square pyramid,  an edgeedge with one Na(15)O6 octahedra,  an edgeedge with one Na(3)O6 octahedra,  an edgeedge with one Na(5)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, edges with two equivalent Na(13)O6 octahedra, edges with two equivalent Na(7)O6 octahedra,  an edgeedge with one Fe(3)O5 square pyramid, and  an edgeedge with one Fe(4)O5 square pyramid. The corner-sharing octahedral tilt angles range from 20-24°. In the tenth Na site, Na(10) is bonded to one O(12), one O(18), one O(4), one O(6), and two equivalent O(14) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Na(16)O6 octahedra,  a cornercorner with one Na(3)O6 octahedra,  a cornercorner with one Na(5)O6 octahedra, corners with two equivalent Na(10)O6 octahedra,  a cornercorner with one Fe(1)O5 square pyramid,  a cornercorner with one Fe(2)O5 square pyramid,  an edgeedge with one Na(16)O6 octahedra,  an edgeedge with one Na(4)O6 octahedra,  an edgeedge with one Na(6)O6 octahedra, edges with two equivalent Na(14)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, edges with two equivalent Na(8)O6 octahedra,  an edgeedge with one Fe(1)O5 square pyramid, and  an edgeedge with one Fe(2)O5 square pyramid. The corner-sharing octahedral tilt angles range from 20-24°. In the eleventh Na site, Na(11) is bonded to one O(10), one O(19), one O(2), one O(7), and two equivalent O(15) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Na(1)O6 octahedra,  a cornercorner with one Na(14)O6 octahedra,  a cornercorner with one Na(8)O6 octahedra, corners with two equivalent Na(11)O6 octahedra,  a cornercorner with one Fe(1)O5 square pyramid,  a cornercorner with one Fe(4)O5 square pyramid,  an edgeedge with one Na(14)O6 octahedra,  an edgeedge with one Na(2)O6 octahedra,  an edgeedge with one Na(7)O6 octahedra, edges with two equivalent Na(15)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, edges with two equivalent Na(6)O6 octahedra,  an edgeedge with one Fe(1)O5 square pyramid, and  an edgeedge with one Fe(4)O5 square pyramid. The corner-sharing octahedral tilt angles range from 20-25°. In the twelfth Na site, Na(12) is bonded to one O(1), one O(20), one O(8), one O(9), and two equivalent O(16) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Na(13)O6 octahedra,  a cornercorner with one Na(2)O6 octahedra,  a cornercorner with one Na(7)O6 octahedra, corners with two equivalent Na(12)O6 octahedra,  a cornercorner with one Fe(2)O5 square pyramid,  a cornercorner with one Fe(3)O5 square pyramid,  an edgeedge with one Na(1)O6 octahedra,  an edgeedge with one Na(13)O6 octahedra,  an edgeedge with one Na(8)O6 octahedra, edges with two equivalent Na(16)O6 octahedra, edges with two equivalent Na(4)O6 octahedra, edges with two equivalent Na(5)O6 octahedra,  an edgeedge with one Fe(2)O5 square pyramid, and  an edgeedge with one Fe(3)O5 square pyramid. The corner-sharing octahedral tilt angles range from 20-24°. In the thirteenth Na site, Na(13) is bonded to one O(1), one O(13), one O(8), one O(9), and two equivalent O(17) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Na(1)O6 octahedra,  a cornercorner with one Na(12)O6 octahedra,  a cornercorner with one Na(8)O6 octahedra, corners with two equivalent Na(13)O6 octahedra,  a cornercorner with one Fe(3)O5 square pyramid,  a cornercorner with one Fe(4)O5 square pyramid,  an edgeedge with one Na(1)O6 octahedra,  an edgeedge with one Na(12)O6 octahedra,  an edgeedge with one Na(7)O6 octahedra, edges with two equivalent Na(4)O6 octahedra, edges with two equivalent Na(5)O6 octahedra, edges with two equivalent Na(9)O6 octahedra,  an edgeedge with one Fe(2)O5 square pyramid, and  an edgeedge with one Fe(3)O5 square pyramid. The corner-sharing octahedral tilt angles range from 20-24°. In the fourteenth Na site, Na(14) is bonded to one O(10), one O(14), one O(2), one O(7), and two equivalent O(18) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Na(11)O6 octahedra,  a cornercorner with one Na(2)O6 octahedra,  a cornercorner with one Na(7)O6 octahedra, corners with two equivalent Na(14)O6 octahedra,  a cornercorner with one Fe(1)O5 square pyramid,  a cornercorner with one Fe(2)O5 square pyramid,  an edgeedge with one Na(11)O6 octahedra,  an edgeedge with one Na(2)O6 octahedra,  an edgeedge with one Na(8)O6 octahedra, edges with two equivalent Na(10)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, edges with two equivalent Na(6)O6 octahedra,  an edgeedge with one Fe(1)O5 square pyramid, and  an edgeedge with one Fe(4)O5 square pyramid. The corner-sharing octahedral tilt angles range from 20-25°. In the fifteenth Na site, Na(15) is bonded to one O(11), one O(15), one O(3), one O(5), and two equivalent O(19) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Na(3)O6 octahedra,  a cornercorner with one Na(5)O6 octahedra,  a cornercorner with one Na(9)O6 octahedra, corners with two equivalent Na(15)O6 octahedra,  a cornercorner with one Fe(1)O5 square pyramid,  a cornercorner with one Fe(4)O5 square pyramid,  an edgeedge with one Na(3)O6 octahedra,  an edgeedge with one Na(6)O6 octahedra,  an edgeedge with one Na(9)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, edges with two equivalent Na(11)O6 octahedra, edges with two equivalent Na(7)O6 octahedra,  an edgeedge with one Fe(3)O5 square pyramid, and  an edgeedge with one Fe(4)O5 square pyramid. The corner-sharing octahedral tilt angles range from 20-24°. In the sixteenth Na site, Na(16) is bonded to one O(12), one O(16), one O(4), one O(6), and two equivalent O(20) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Na(10)O6 octahedra,  a cornercorner with one Na(4)O6 octahedra,  a cornercorner with one Na(6)O6 octahedra, corners with two equivalent Na(16)O6 octahedra,  a cornercorner with one Fe(2)O5 square pyramid,  a cornercorner with one Fe(3)O5 square pyramid,  an edgeedge with one Na(10)O6 octahedra,  an edgeedge with one Na(4)O6 octahedra,  an edgeedge with one Na(5)O6 octahedra, edges with two equivalent Na(12)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, edges with two equivalent Na(8)O6 octahedra,  an edgeedge with one Fe(1)O5 square pyramid, and  an edgeedge with one Fe(2)O5 square pyramid. The corner-sharing octahedral tilt angles range from 20-24°. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(12), one O(15), one O(18), one O(2), and one O(6) atom to form FeO5 square pyramids that share  a cornercorner with one Na(10)O6 octahedra,  a cornercorner with one Na(11)O6 octahedra,  a cornercorner with one Na(14)O6 octahedra,  a cornercorner with one Na(15)O6 octahedra,  a cornercorner with one Na(2)O6 octahedra,  a cornercorner with one Na(4)O6 octahedra,  a cornercorner with one Na(6)O6 octahedra,  a cornercorner with one Na(8)O6 octahedra,  an edgeedge with one Na(10)O6 octahedra,  an edgeedge with one Na(11)O6 octahedra,  an edgeedge with one Na(14)O6 octahedra,  an edgeedge with one Na(16)O6 octahedra,  an edgeedge with one Na(2)O6 octahedra,  an edgeedge with one Na(3)O6 octahedra,  an edgeedge with one Na(6)O6 octahedra, and  an edgeedge with one Na(8)O6 octahedra. The corner-sharing octahedral tilt angles range from 10-71°. In the second Fe site, Fe(2) is bonded to one O(14), one O(20), one O(4), one O(8), and one O(9) atom to form FeO5 square pyramids that share  a cornercorner with one Na(1)O6 octahedra,  a cornercorner with one Na(10)O6 octahedra,  a cornercorner with one Na(12)O6 octahedra,  a cornercorner with one Na(14)O6 octahedra,  a cornercorner with one Na(16)O6 octahedra,  a cornercorner with one Na(4)O6 octahedra,  a cornercorner with one Na(5)O6 octahedra,  a cornercorner with one Na(8)O6 octahedra,  an edgeedge with one Na(10)O6 octahedra,  an edgeedge with one Na(12)O6 octahedra,  an edgeedge with one Na(13)O6 octahedra,  an edgeedge with one Na(16)O6 octahedra,  an edgeedge with one Na(2)O6 octahedra,  an edgeedge with one Na(4)O6 octahedra,  an edgeedge with one Na(5)O6 octahedra, and  an edgeedge with one Na(8)O6 octahedra. The corner-sharing octahedral tilt angles range from 10-71°. In the third Fe site, Fe(3) is bonded to one O(1), one O(11), one O(16), one O(17), and one O(5) atom to form FeO5 square pyramids that share  a cornercorner with one Na(1)O6 octahedra,  a cornercorner with one Na(12)O6 octahedra,  a cornercorner with one Na(13)O6 octahedra,  a cornercorner with one Na(16)O6 octahedra,  a cornercorner with one Na(3)O6 octahedra,  a cornercorner with one Na(5)O6 octahedra,  a cornercorner with one Na(7)O6 octahedra,  a cornercorner with one Na(9)O6 octahedra,  an edgeedge with one Na(1)O6 octahedra,  an edgeedge with one Na(12)O6 octahedra,  an edgeedge with one Na(13)O6 octahedra,  an edgeedge with one Na(15)O6 octahedra,  an edgeedge with one Na(4)O6 octahedra,  an edgeedge with one Na(5)O6 octahedra,  an edgeedge with one Na(7)O6 octahedra, and  an edgeedge with one Na(9)O6 octahedra. The corner-sharing octahedral tilt angles range from 10-71°. In the fourth Fe site, Fe(4) is bonded to one O(10), one O(13), one O(19), one O(3), and one O(7) atom to form FeO5 square pyramids that share  a cornercorner with one Na(11)O6 octahedra,  a cornercorner with one Na(13)O6 octahedra,  a cornercorner with one Na(15)O6 octahedra,  a cornercorner with one Na(2)O6 octahedra,  a cornercorner with one Na(3)O6 octahedra,  a cornercorner with one Na(6)O6 octahedra,  a cornercorner with one Na(7)O6 octahedra,  a cornercorner with one Na(9)O6 octahedra,  an edgeedge with one Na(1)O6 octahedra,  an edgeedge with one Na(11)O6 octahedra,  an edgeedge with one Na(14)O6 octahedra,  an edgeedge with one Na(15)O6 octahedra,  an edgeedge with one Na(3)O6 octahedra,  an edgeedge with one Na(6)O6 octahedra,  an edgeedge with one Na(7)O6 octahedra, and  an edgeedge with one Na(9)O6 octahedra. The corner-sharing octahedral tilt angles range from 10-71°. There are twenty inequivalent O sites. In the first O site, O(1) is bonded in a distorted square pyramidal geometry to one Na(1), one Na(12), one Na(13), one Na(7), and one Fe(3) atom. In the second O site, O(2) is bonded in a distorted square pyramidal geometry to one Na(11), one Na(14), one Na(2), one Na(8), and one Fe(1) atom. In the third O site, O(3) is bonded in a distorted square pyramidal geometry to one Na(15), one Na(3), one Na(6), one Na(9), and one Fe(4) atom. In the fourth O site, O(4) is bonded in a distorted square pyramidal geometry to one Na(10), one Na(16), one Na(4), one Na(5), and one Fe(2) atom. In the fifth O site, O(5) is bonded in a 6-coordinate geometry to one Na(15), one Na(5), one Na(9), two equivalent Na(1), and one Fe(3) atom. In the sixth O site, O(6) is bonded in a 6-coordinate geometry to one Na(10), one Na(16), one Na(6), two equivalent Na(2), and one Fe(1) atom. In the seventh O site, O(7) is bonded in a 6-coordinate geometry to one Na(11), one Na(14), one Na(7), two equivalent Na(3), and one Fe(4) atom. In the eighth O site, O(8) is bonded in a 6-coordinate geometry to one Na(12), one Na(13), one Na(8), two equivalent Na(4), and one Fe(2) atom. In the ninth O site, O(9) is bonded in a 6-coordinate geometry to one Na(1), one Na(12), one Na(13), two equivalent Na(5), and one Fe(2) atom. In the tenth O site, O(10) is bonded in a 6-coordinate geometry to one Na(11), one Na(14), one Na(2), two equivalent Na(6), and one Fe(4) atom. In the eleventh O site, O(11) is bonded in a 6-coordinate geometry to one Na(15), one Na(3), one Na(9), two equivalent Na(7), and one Fe(3) atom. In the twelfth O site, O(12) is bonded in a 6-coordinate geometry to one Na(10), one Na(16), one Na(4), two equivalent Na(8), and one Fe(1) atom. In the thirteenth O site, O(13) is bonded in a 6-coordinate geometry to one Na(1), one Na(13), one Na(7), two equivalent Na(9), and one Fe(4) atom. In the fourteenth O site, O(14) is bonded in a 6-coordinate geometry to one Na(14), one Na(2), one Na(8), two equivalent Na(10), and one Fe(2) atom. In the fifteenth O site, O(15) is bonded in a 6-coordinate geometry to one Na(15), one Na(3), one Na(6), two equivalent Na(11), and one Fe(1) atom. In the sixteenth O site, O(16) is bonded in a 6-coordinate geometry to one Na(16), one Na(4), one Na(5), two equivalent Na(12), and one Fe(3) atom. In the seventeenth O site, O(17) is bonded in a 6-coordinate geometry to one Na(4), one Na(5), one Na(9), two equivalent Na(13), and one Fe(3) atom. In the eighteenth O site, O(18) is bonded in a 6-coordinate geometry to one Na(10), one Na(3), one Na(6), two equivalent Na(14), and one Fe(1) atom. In the nineteenth O site, O(19) is bonded in a 6-coordinate geometry to one Na(1), one Na(11), one Na(7), two equivalent Na(15), and one Fe(4) atom. In the twentieth O site, O(20) is bonded in a 6-coordinate geometry to one Na(12), one Na(2), one Na(8), two equivalent Na(16), and one Fe(2) atom.
Na4FeO5 crystallizes in the triclinic P1 space group. There are sixteen inequivalent Na sites. In the first Na site, Na(1) is bonded to one O(1), one O(13), one O(19), one O(9), and two equivalent O(5) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Na(11)O6 octahedra,  a cornercorner with one Na(13)O6 octahedra,  a cornercorner with one Na(7)O6 octahedra, corners with two equivalent Na(1)O6 octahedra,  a cornercorner with one Fe(2)O5 square pyramid,  a cornercorner with one Fe(3)O5 square pyramid,  an edgeedge with one Na(12)O6 octahedra,  an edgeedge with one Na(13)O6 octahedra,  an edgeedge with one Na(7)O6 octahedra, edges with two equivalent Na(15)O6 octahedra, edges with two equivalent Na(5)O6 octahedra, edges with two equivalent Na(9)O6 octahedra,  an edgeedge with one Fe(3)O5 square pyramid, and  an edgeedge with one Fe(4)O5 square pyramid. The corner-sharing octahedral tilt angles range from 20-24°. The Na(1)-O(1) bond length is 2.28 Å. The Na(1)-O(13) bond length is 2.33 Å. The Na(1)-O(19) bond length is 2.42 Å. The Na(1)-O(9) bond length is 2.76 Å. There is one shorter (2.42 Å) and one longer (2.53 Å) Na(1)-O(5) bond length. In the second Na site, Na(2) is bonded to one O(10), one O(14), one O(2), one O(20), and two equivalent O(6) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Na(12)O6 octahedra,  a cornercorner with one Na(14)O6 octahedra,  a cornercorner with one Na(8)O6 octahedra, corners with two equivalent Na(2)O6 octahedra,  a cornercorner with one Fe(1)O5 square pyramid,  a cornercorner with one Fe(4)O5 square pyramid,  an edgeedge with one Na(11)O6 octahedra,  an edgeedge with one Na(14)O6 octahedra,  an edgeedge with one Na(8)O6 octahedra, edges with two equivalent Na(10)O6 octahedra, edges with two equivalent Na(16)O6 octahedra, edges with two equivalent Na(6)O6 octahedra,  an edgeedge with one Fe(1)O5 square pyramid, and  an edgeedge with one Fe(2)O5 square pyramid. The corner-sharing octahedral tilt angles range from 20-24°. The Na(2)-O(10) bond length is 2.77 Å. The Na(2)-O(14) bond length is 2.33 Å. The Na(2)-O(2) bond length is 2.28 Å. The Na(2)-O(20) bond length is 2.42 Å. There is one shorter (2.42 Å) and one longer (2.53 Å) Na(2)-O(6) bond length. In the third Na site, Na(3) is bonded to one O(11), one O(15), one O(18), one O(3), and two equivalent O(7) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Na(10)O6 octahedra,  a cornercorner with one Na(15)O6 octahedra,  a cornercorner with one Na(6)O6 octahedra, corners with two equivalent Na(3)O6 octahedra,  a cornercorner with one Fe(3)O5 square pyramid,  a cornercorner with one Fe(4)O5 square pyramid,  an edgeedge with one Na(15)O6 octahedra,  an edgeedge with one Na(6)O6 octahedra,  an edgeedge with one Na(9)O6 octahedra, edges with two equivalent Na(11)O6 octahedra, edges with two equivalent Na(14)O6 octahedra, edges with two equivalent Na(7)O6 octahedra,  an edgeedge with one Fe(1)O5 square pyramid, and  an edgeedge with one Fe(4)O5 square pyramid. The corner-sharing octahedral tilt angles range from 20-25°. The Na(3)-O(11) bond length is 2.76 Å. The Na(3)-O(15) bond length is 2.33 Å. The Na(3)-O(18) bond length is 2.42 Å. The Na(3)-O(3) bond length is 2.29 Å. There is one shorter (2.42 Å) and one longer (2.53 Å) Na(3)-O(7) bond length. In the fourth Na site, Na(4) is bonded to one O(12), one O(16), one O(17), one O(4), and two equivalent O(8) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Na(16)O6 octahedra,  a cornercorner with one Na(5)O6 octahedra,  a cornercorner with one Na(9)O6 octahedra, corners with two equivalent Na(4)O6 octahedra,  a cornercorner with one Fe(1)O5 square pyramid,  a cornercorner with one Fe(2)O5 square pyramid,  an edgeedge with one Na(10)O6 octahedra,  an edgeedge with one Na(16)O6 octahedra,  an edgeedge with one Na(5)O6 octahedra, edges with two equivalent Na(12)O6 octahedra, edges with two equivalent Na(13)O6 octahedra, edges with two equivalent Na(8)O6 octahedra,  an edgeedge with one Fe(2)O5 square pyramid, and  an edgeedge with one Fe(3)O5 square pyramid. The corner-sharing octahedral tilt angles range from 20-25°. The Na(4)-O(12) bond length is 2.76 Å. The Na(4)-O(16) bond length is 2.33 Å. The Na(4)-O(17) bond length is 2.42 Å. The Na(4)-O(4) bond length is 2.29 Å. There is one shorter (2.42 Å) and one longer (2.53 Å) Na(4)-O(8) bond length. In the fifth Na site, Na(5) is bonded to one O(16), one O(17), one O(4), one O(5), and two equivalent O(9) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Na(10)O6 octahedra,  a cornercorner with one Na(15)O6 octahedra,  a cornercorner with one Na(4)O6 octahedra, corners with two equivalent Na(5)O6 octahedra,  a cornercorner with one Fe(2)O5 square pyramid,  a cornercorner with one Fe(3)O5 square pyramid,  an edgeedge with one Na(16)O6 octahedra,  an edgeedge with one Na(4)O6 octahedra,  an edgeedge with one Na(9)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, edges with two equivalent Na(12)O6 octahedra, edges with two equivalent Na(13)O6 octahedra,  an edgeedge with one Fe(2)O5 square pyramid, and  an edgeedge with one Fe(3)O5 square pyramid. The corner-sharing octahedral tilt angles range from 20-25°. The Na(5)-O(16) bond length is 2.42 Å. The Na(5)-O(17) bond length is 2.77 Å. The Na(5)-O(4) bond length is 2.29 Å. The Na(5)-O(5) bond length is 2.33 Å. There is one shorter (2.42 Å) and one longer (2.53 Å) Na(5)-O(9) bond length. In the sixth Na site, Na(6) is bonded to one O(15), one O(18), one O(3), one O(6), and two equivalent O(10) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Na(16)O6 octahedra,  a cornercorner with one Na(3)O6 octahedra,  a cornercorner with one Na(9)O6 octahedra, corners with two equivalent Na(6)O6 octahedra,  a cornercorner with one Fe(1)O5 square pyramid,  a cornercorner with one Fe(4)O5 square pyramid,  an edgeedge with one Na(10)O6 octahedra,  an edgeedge with one Na(15)O6 octahedra,  an edgeedge with one Na(3)O6 octahedra, edges with two equivalent Na(11)O6 octahedra, edges with two equivalent Na(14)O6 octahedra, edges with two equivalent Na(2)O6 octahedra,  an edgeedge with one Fe(1)O5 square pyramid, and  an edgeedge with one Fe(4)O5 square pyramid. The corner-sharing octahedral tilt angles range from 20-25°. The Na(6)-O(15) bond length is 2.42 Å. The Na(6)-O(18) bond length is 2.77 Å. The Na(6)-O(3) bond length is 2.29 Å. The Na(6)-O(6) bond length is 2.33 Å. There is one shorter (2.42 Å) and one longer (2.53 Å) Na(6)-O(10) bond length. In the seventh Na site, Na(7) is bonded to one O(1), one O(13), one O(19), one O(7), and two equivalent O(11) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Na(1)O6 octahedra,  a cornercorner with one Na(12)O6 octahedra,  a cornercorner with one Na(14)O6 octahedra, corners with two equivalent Na(7)O6 octahedra,  a cornercorner with one Fe(3)O5 square pyramid,  a cornercorner with one Fe(4)O5 square pyramid,  an edgeedge with one Na(1)O6 octahedra,  an edgeedge with one Na(11)O6 octahedra,  an edgeedge with one Na(13)O6 octahedra, edges with two equivalent Na(15)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, edges with two equivalent Na(9)O6 octahedra,  an edgeedge with one Fe(3)O5 square pyramid, and  an edgeedge with one Fe(4)O5 square pyramid. The corner-sharing octahedral tilt angles range from 20-24°. The Na(7)-O(1) bond length is 2.28 Å. The Na(7)-O(13) bond length is 2.42 Å. The Na(7)-O(19) bond length is 2.77 Å. The Na(7)-O(7) bond length is 2.33 Å. There is one shorter (2.42 Å) and one longer (2.53 Å) Na(7)-O(11) bond length. In the eighth Na site, Na(8) is bonded to one O(14), one O(2), one O(20), one O(8), and two equivalent O(12) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Na(11)O6 octahedra,  a cornercorner with one Na(13)O6 octahedra,  a cornercorner with one Na(2)O6 octahedra, corners with two equivalent Na(8)O6 octahedra,  a cornercorner with one Fe(1)O5 square pyramid,  a cornercorner with one Fe(2)O5 square pyramid,  an edgeedge with one Na(12)O6 octahedra,  an edgeedge with one Na(14)O6 octahedra,  an edgeedge with one Na(2)O6 octahedra, edges with two equivalent Na(10)O6 octahedra, edges with two equivalent Na(16)O6 octahedra, edges with two equivalent Na(4)O6 octahedra,  an edgeedge with one Fe(1)O5 square pyramid, and  an edgeedge with one Fe(2)O5 square pyramid. The corner-sharing octahedral tilt angles range from 20-24°. The Na(8)-O(14) bond length is 2.42 Å. The Na(8)-O(2) bond length is 2.29 Å. The Na(8)-O(20) bond length is 2.76 Å. The Na(8)-O(8) bond length is 2.33 Å. There is one shorter (2.42 Å) and one longer (2.53 Å) Na(8)-O(12) bond length. In the ninth Na site, Na(9) is bonded to one O(11), one O(17), one O(3), one O(5), and two equivalent O(13) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Na(15)O6 octahedra,  a cornercorner with one Na(4)O6 octahedra,  a cornercorner with one Na(6)O6 octahedra, corners with two equivalent Na(9)O6 octahedra,  a cornercorner with one Fe(3)O5 square pyramid,  a cornercorner with one Fe(4)O5 square pyramid,  an edgeedge with one Na(15)O6 octahedra,  an edgeedge with one Na(3)O6 octahedra,  an edgeedge with one Na(5)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, edges with two equivalent Na(13)O6 octahedra, edges with two equivalent Na(7)O6 octahedra,  an edgeedge with one Fe(3)O5 square pyramid, and  an edgeedge with one Fe(4)O5 square pyramid. The corner-sharing octahedral tilt angles range from 20-24°. The Na(9)-O(11) bond length is 2.42 Å. The Na(9)-O(17) bond length is 2.33 Å. The Na(9)-O(3) bond length is 2.29 Å. The Na(9)-O(5) bond length is 2.77 Å. There is one shorter (2.42 Å) and one longer (2.53 Å) Na(9)-O(13) bond length. In the tenth Na site, Na(10) is bonded to one O(12), one O(18), one O(4), one O(6), and two equivalent O(14) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Na(16)O6 octahedra,  a cornercorner with one Na(3)O6 octahedra,  a cornercorner with one Na(5)O6 octahedra, corners with two equivalent Na(10)O6 octahedra,  a cornercorner with one Fe(1)O5 square pyramid,  a cornercorner with one Fe(2)O5 square pyramid,  an edgeedge with one Na(16)O6 octahedra,  an edgeedge with one Na(4)O6 octahedra,  an edgeedge with one Na(6)O6 octahedra, edges with two equivalent Na(14)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, edges with two equivalent Na(8)O6 octahedra,  an edgeedge with one Fe(1)O5 square pyramid, and  an edgeedge with one Fe(2)O5 square pyramid. The corner-sharing octahedral tilt angles range from 20-24°. The Na(10)-O(12) bond length is 2.41 Å. The Na(10)-O(18) bond length is 2.33 Å. The Na(10)-O(4) bond length is 2.29 Å. The Na(10)-O(6) bond length is 2.77 Å. There is one shorter (2.42 Å) and one longer (2.53 Å) Na(10)-O(14) bond length. In the eleventh Na site, Na(11) is bonded to one O(10), one O(19), one O(2), one O(7), and two equivalent O(15) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Na(1)O6 octahedra,  a cornercorner with one Na(14)O6 octahedra,  a cornercorner with one Na(8)O6 octahedra, corners with two equivalent Na(11)O6 octahedra,  a cornercorner with one Fe(1)O5 square pyramid,  a cornercorner with one Fe(4)O5 square pyramid,  an edgeedge with one Na(14)O6 octahedra,  an edgeedge with one Na(2)O6 octahedra,  an edgeedge with one Na(7)O6 octahedra, edges with two equivalent Na(15)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, edges with two equivalent Na(6)O6 octahedra,  an edgeedge with one Fe(1)O5 square pyramid, and  an edgeedge with one Fe(4)O5 square pyramid. The corner-sharing octahedral tilt angles range from 20-25°. The Na(11)-O(10) bond length is 2.42 Å. The Na(11)-O(19) bond length is 2.33 Å. The Na(11)-O(2) bond length is 2.28 Å. The Na(11)-O(7) bond length is 2.77 Å. There is one shorter (2.42 Å) and one longer (2.53 Å) Na(11)-O(15) bond length. In the twelfth Na site, Na(12) is bonded to one O(1), one O(20), one O(8), one O(9), and two equivalent O(16) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Na(13)O6 octahedra,  a cornercorner with one Na(2)O6 octahedra,  a cornercorner with one Na(7)O6 octahedra, corners with two equivalent Na(12)O6 octahedra,  a cornercorner with one Fe(2)O5 square pyramid,  a cornercorner with one Fe(3)O5 square pyramid,  an edgeedge with one Na(1)O6 octahedra,  an edgeedge with one Na(13)O6 octahedra,  an edgeedge with one Na(8)O6 octahedra, edges with two equivalent Na(16)O6 octahedra, edges with two equivalent Na(4)O6 octahedra, edges with two equivalent Na(5)O6 octahedra,  an edgeedge with one Fe(2)O5 square pyramid, and  an edgeedge with one Fe(3)O5 square pyramid. The corner-sharing octahedral tilt angles range from 20-24°. The Na(12)-O(1) bond length is 2.29 Å. The Na(12)-O(20) bond length is 2.33 Å. The Na(12)-O(8) bond length is 2.75 Å. The Na(12)-O(9) bond length is 2.42 Å. There is one shorter (2.42 Å) and one longer (2.53 Å) Na(12)-O(16) bond length. In the thirteenth Na site, Na(13) is bonded to one O(1), one O(13), one O(8), one O(9), and two equivalent O(17) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Na(1)O6 octahedra,  a cornercorner with one Na(12)O6 octahedra,  a cornercorner with one Na(8)O6 octahedra, corners with two equivalent Na(13)O6 octahedra,  a cornercorner with one Fe(3)O5 square pyramid,  a cornercorner with one Fe(4)O5 square pyramid,  an edgeedge with one Na(1)O6 octahedra,  an edgeedge with one Na(12)O6 octahedra,  an edgeedge with one Na(7)O6 octahedra, edges with two equivalent Na(4)O6 octahedra, edges with two equivalent Na(5)O6 octahedra, edges with two equivalent Na(9)O6 octahedra,  an edgeedge with one Fe(2)O5 square pyramid, and  an edgeedge with one Fe(3)O5 square pyramid. The corner-sharing octahedral tilt angles range from 20-24°. The Na(13)-O(1) bond length is 2.29 Å. The Na(13)-O(13) bond length is 2.76 Å. The Na(13)-O(8) bond length is 2.41 Å. The Na(13)-O(9) bond length is 2.34 Å. There is one shorter (2.42 Å) and one longer (2.53 Å) Na(13)-O(17) bond length. In the fourteenth Na site, Na(14) is bonded to one O(10), one O(14), one O(2), one O(7), and two equivalent O(18) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Na(11)O6 octahedra,  a cornercorner with one Na(2)O6 octahedra,  a cornercorner with one Na(7)O6 octahedra, corners with two equivalent Na(14)O6 octahedra,  a cornercorner with one Fe(1)O5 square pyramid,  a cornercorner with one Fe(2)O5 square pyramid,  an edgeedge with one Na(11)O6 octahedra,  an edgeedge with one Na(2)O6 octahedra,  an edgeedge with one Na(8)O6 octahedra, edges with two equivalent Na(10)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, edges with two equivalent Na(6)O6 octahedra,  an edgeedge with one Fe(1)O5 square pyramid, and  an edgeedge with one Fe(4)O5 square pyramid. The corner-sharing octahedral tilt angles range from 20-25°. The Na(14)-O(10) bond length is 2.33 Å. The Na(14)-O(14) bond length is 2.76 Å. The Na(14)-O(2) bond length is 2.29 Å. The Na(14)-O(7) bond length is 2.42 Å. There is one shorter (2.42 Å) and one longer (2.53 Å) Na(14)-O(18) bond length. In the fifteenth Na site, Na(15) is bonded to one O(11), one O(15), one O(3), one O(5), and two equivalent O(19) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Na(3)O6 octahedra,  a cornercorner with one Na(5)O6 octahedra,  a cornercorner with one Na(9)O6 octahedra, corners with two equivalent Na(15)O6 octahedra,  a cornercorner with one Fe(1)O5 square pyramid,  a cornercorner with one Fe(4)O5 square pyramid,  an edgeedge with one Na(3)O6 octahedra,  an edgeedge with one Na(6)O6 octahedra,  an edgeedge with one Na(9)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, edges with two equivalent Na(11)O6 octahedra, edges with two equivalent Na(7)O6 octahedra,  an edgeedge with one Fe(3)O5 square pyramid, and  an edgeedge with one Fe(4)O5 square pyramid. The corner-sharing octahedral tilt angles range from 20-24°. The Na(15)-O(11) bond length is 2.33 Å. The Na(15)-O(15) bond length is 2.77 Å. The Na(15)-O(3) bond length is 2.29 Å. The Na(15)-O(5) bond length is 2.42 Å. There is one shorter (2.42 Å) and one longer (2.53 Å) Na(15)-O(19) bond length. In the sixteenth Na site, Na(16) is bonded to one O(12), one O(16), one O(4), one O(6), and two equivalent O(20) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Na(10)O6 octahedra,  a cornercorner with one Na(4)O6 octahedra,  a cornercorner with one Na(6)O6 octahedra, corners with two equivalent Na(16)O6 octahedra,  a cornercorner with one Fe(2)O5 square pyramid,  a cornercorner with one Fe(3)O5 square pyramid,  an edgeedge with one Na(10)O6 octahedra,  an edgeedge with one Na(4)O6 octahedra,  an edgeedge with one Na(5)O6 octahedra, edges with two equivalent Na(12)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, edges with two equivalent Na(8)O6 octahedra,  an edgeedge with one Fe(1)O5 square pyramid, and  an edgeedge with one Fe(2)O5 square pyramid. The corner-sharing octahedral tilt angles range from 20-24°. The Na(16)-O(12) bond length is 2.33 Å. The Na(16)-O(16) bond length is 2.77 Å. The Na(16)-O(4) bond length is 2.29 Å. The Na(16)-O(6) bond length is 2.41 Å. There is one shorter (2.42 Å) and one longer (2.53 Å) Na(16)-O(20) bond length. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(12), one O(15), one O(18), one O(2), and one O(6) atom to form FeO5 square pyramids that share  a cornercorner with one Na(10)O6 octahedra,  a cornercorner with one Na(11)O6 octahedra,  a cornercorner with one Na(14)O6 octahedra,  a cornercorner with one Na(15)O6 octahedra,  a cornercorner with one Na(2)O6 octahedra,  a cornercorner with one Na(4)O6 octahedra,  a cornercorner with one Na(6)O6 octahedra,  a cornercorner with one Na(8)O6 octahedra,  an edgeedge with one Na(10)O6 octahedra,  an edgeedge with one Na(11)O6 octahedra,  an edgeedge with one Na(14)O6 octahedra,  an edgeedge with one Na(16)O6 octahedra,  an edgeedge with one Na(2)O6 octahedra,  an edgeedge with one Na(3)O6 octahedra,  an edgeedge with one Na(6)O6 octahedra, and  an edgeedge with one Na(8)O6 octahedra. The corner-sharing octahedral tilt angles range from 10-71°. The Fe(1)-O(12) bond length is 1.84 Å. The Fe(1)-O(15) bond length is 1.84 Å. The Fe(1)-O(18) bond length is 1.84 Å. The Fe(1)-O(2) bond length is 1.77 Å. The Fe(1)-O(6) bond length is 1.84 Å. In the second Fe site, Fe(2) is bonded to one O(14), one O(20), one O(4), one O(8), and one O(9) atom to form FeO5 square pyramids that share  a cornercorner with one Na(1)O6 octahedra,  a cornercorner with one Na(10)O6 octahedra,  a cornercorner with one Na(12)O6 octahedra,  a cornercorner with one Na(14)O6 octahedra,  a cornercorner with one Na(16)O6 octahedra,  a cornercorner with one Na(4)O6 octahedra,  a cornercorner with one Na(5)O6 octahedra,  a cornercorner with one Na(8)O6 octahedra,  an edgeedge with one Na(10)O6 octahedra,  an edgeedge with one Na(12)O6 octahedra,  an edgeedge with one Na(13)O6 octahedra,  an edgeedge with one Na(16)O6 octahedra,  an edgeedge with one Na(2)O6 octahedra,  an edgeedge with one Na(4)O6 octahedra,  an edgeedge with one Na(5)O6 octahedra, and  an edgeedge with one Na(8)O6 octahedra. The corner-sharing octahedral tilt angles range from 10-71°. The Fe(2)-O(14) bond length is 1.85 Å. The Fe(2)-O(20) bond length is 1.85 Å. The Fe(2)-O(4) bond length is 1.78 Å. The Fe(2)-O(8) bond length is 1.85 Å. The Fe(2)-O(9) bond length is 1.85 Å. In the third Fe site, Fe(3) is bonded to one O(1), one O(11), one O(16), one O(17), and one O(5) atom to form FeO5 square pyramids that share  a cornercorner with one Na(1)O6 octahedra,  a cornercorner with one Na(12)O6 octahedra,  a cornercorner with one Na(13)O6 octahedra,  a cornercorner with one Na(16)O6 octahedra,  a cornercorner with one Na(3)O6 octahedra,  a cornercorner with one Na(5)O6 octahedra,  a cornercorner with one Na(7)O6 octahedra,  a cornercorner with one Na(9)O6 octahedra,  an edgeedge with one Na(1)O6 octahedra,  an edgeedge with one Na(12)O6 octahedra,  an edgeedge with one Na(13)O6 octahedra,  an edgeedge with one Na(15)O6 octahedra,  an edgeedge with one Na(4)O6 octahedra,  an edgeedge with one Na(5)O6 octahedra,  an edgeedge with one Na(7)O6 octahedra, and  an edgeedge with one Na(9)O6 octahedra. The corner-sharing octahedral tilt angles range from 10-71°. The Fe(3)-O(1) bond length is 1.77 Å. The Fe(3)-O(11) bond length is 1.84 Å. The Fe(3)-O(16) bond length is 1.84 Å. The Fe(3)-O(17) bond length is 1.84 Å. The Fe(3)-O(5) bond length is 1.84 Å. In the fourth Fe site, Fe(4) is bonded to one O(10), one O(13), one O(19), one O(3), and one O(7) atom to form FeO5 square pyramids that share  a cornercorner with one Na(11)O6 octahedra,  a cornercorner with one Na(13)O6 octahedra,  a cornercorner with one Na(15)O6 octahedra,  a cornercorner with one Na(2)O6 octahedra,  a cornercorner with one Na(3)O6 octahedra,  a cornercorner with one Na(6)O6 octahedra,  a cornercorner with one Na(7)O6 octahedra,  a cornercorner with one Na(9)O6 octahedra,  an edgeedge with one Na(1)O6 octahedra,  an edgeedge with one Na(11)O6 octahedra,  an edgeedge with one Na(14)O6 octahedra,  an edgeedge with one Na(15)O6 octahedra,  an edgeedge with one Na(3)O6 octahedra,  an edgeedge with one Na(6)O6 octahedra,  an edgeedge with one Na(7)O6 octahedra, and  an edgeedge with one Na(9)O6 octahedra. The corner-sharing octahedral tilt angles range from 10-71°. The Fe(4)-O(10) bond length is 1.84 Å. The Fe(4)-O(13) bond length is 1.84 Å. The Fe(4)-O(19) bond length is 1.84 Å. The Fe(4)-O(3) bond length is 1.77 Å. The Fe(4)-O(7) bond length is 1.84 Å. There are twenty inequivalent O sites. In the first O site, O(1) is bonded in a distorted square pyramidal geometry to one Na(1), one Na(12), one Na(13), one Na(7), and one Fe(3) atom. In the second O site, O(2) is bonded in a distorted square pyramidal geometry to one Na(11), one Na(14), one Na(2), one Na(8), and one Fe(1) atom. In the third O site, O(3) is bonded in a distorted square pyramidal geometry to one Na(15), one Na(3), one Na(6), one Na(9), and one Fe(4) atom. In the fourth O site, O(4) is bonded in a distorted square pyramidal geometry to one Na(10), one Na(16), one Na(4), one Na(5), and one Fe(2) atom. In the fifth O site, O(5) is bonded in a 6-coordinate geometry to one Na(15), one Na(5), one Na(9), two equivalent Na(1), and one Fe(3) atom. In the sixth O site, O(6) is bonded in a 6-coordinate geometry to one Na(10), one Na(16), one Na(6), two equivalent Na(2), and one Fe(1) atom. In the seventh O site, O(7) is bonded in a 6-coordinate geometry to one Na(11), one Na(14), one Na(7), two equivalent Na(3), and one Fe(4) atom. In the eighth O site, O(8) is bonded in a 6-coordinate geometry to one Na(12), one Na(13), one Na(8), two equivalent Na(4), and one Fe(2) atom. In the ninth O site, O(9) is bonded in a 6-coordinate geometry to one Na(1), one Na(12), one Na(13), two equivalent Na(5), and one Fe(2) atom. In the tenth O site, O(10) is bonded in a 6-coordinate geometry to one Na(11), one Na(14), one Na(2), two equivalent Na(6), and one Fe(4) atom. In the eleventh O site, O(11) is bonded in a 6-coordinate geometry to one Na(15), one Na(3), one Na(9), two equivalent Na(7), and one Fe(3) atom. In the twelfth O site, O(12) is bonded in a 6-coordinate geometry to one Na(10), one Na(16), one Na(4), two equivalent Na(8), and one Fe(1) atom. In the thirteenth O site, O(13) is bonded in a 6-coordinate geometry to one Na(1), one Na(13), one Na(7), two equivalent Na(9), and one Fe(4) atom. In the fourteenth O site, O(14) is bonded in a 6-coordinate geometry to one Na(14), one Na(2), one Na(8), two equivalent Na(10), and one Fe(2) atom. In the fifteenth O site, O(15) is bonded in a 6-coordinate geometry to one Na(15), one Na(3), one Na(6), two equivalent Na(11), and one Fe(1) atom. In the sixteenth O site, O(16) is bonded in a 6-coordinate geometry to one Na(16), one Na(4), one Na(5), two equivalent Na(12), and one Fe(3) atom. In the seventeenth O site, O(17) is bonded in a 6-coordinate geometry to one Na(4), one Na(5), one Na(9), two equivalent Na(13), and one Fe(3) atom. In the eighteenth O site, O(18) is bonded in a 6-coordinate geometry to one Na(10), one Na(3), one Na(6), two equivalent Na(14), and one Fe(1) atom. In the nineteenth O site, O(19) is bonded in a 6-coordinate geometry to one Na(1), one Na(11), one Na(7), two equivalent Na(15), and one Fe(4) atom. In the twentieth O site, O(20) is bonded in a 6-coordinate geometry to one Na(12), one Na(2), one Na(8), two equivalent Na(16), and one Fe(2) atom.