Na2FeO3 is Caswellsilverite-like structured and crystallizes in the monoclinic P2 space group. There are eight inequivalent Na sites. In the first Na site, Na(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(5) atoms to form distorted NaO6 octahedra that share corners with two equivalent Na(4)O6 octahedra, corners with two equivalent Fe(1)O6 octahedra, corners with two equivalent Fe(4)O6 octahedra,  an edgeedge with one Na(5)O6 octahedra,  an edgeedge with one Na(7)O6 octahedra, edges with two equivalent Na(4)O6 octahedra, edges with two equivalent Na(6)O6 octahedra, edges with two equivalent Na(8)O6 octahedra, edges with two equivalent Fe(2)O6 octahedra, and edges with two equivalent Fe(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 11-17°. In the second Na site, Na(2) is bonded to two equivalent O(2), two equivalent O(4), and two equivalent O(6) atoms to form distorted NaO6 octahedra that share corners with two equivalent Na(3)O6 octahedra, corners with two equivalent Fe(2)O6 octahedra, corners with two equivalent Fe(3)O6 octahedra,  an edgeedge with one Na(6)O6 octahedra,  an edgeedge with one Na(8)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, edges with two equivalent Na(5)O6 octahedra, edges with two equivalent Na(7)O6 octahedra, edges with two equivalent Fe(1)O6 octahedra, and edges with two equivalent Fe(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 10-17°. In the third Na site, Na(3) is bonded to two equivalent O(2), two equivalent O(4), and two equivalent O(6) atoms to form NaO6 octahedra that share corners with two equivalent Na(2)O6 octahedra, corners with two equivalent Na(6)O6 octahedra, corners with two equivalent Na(8)O6 octahedra,  an edgeedge with one Fe(2)O6 octahedra,  an edgeedge with one Fe(3)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, edges with two equivalent Na(5)O6 octahedra, edges with two equivalent Na(7)O6 octahedra, edges with two equivalent Fe(1)O6 octahedra, and edges with two equivalent Fe(4)O6 octahedra. The corner-sharing octahedral tilt angles are 17°. In the fourth Na site, Na(4) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(5) atoms to form NaO6 octahedra that share corners with two equivalent Na(1)O6 octahedra, corners with two equivalent Na(5)O6 octahedra, corners with two equivalent Na(7)O6 octahedra,  an edgeedge with one Fe(1)O6 octahedra,  an edgeedge with one Fe(4)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, edges with two equivalent Na(6)O6 octahedra, edges with two equivalent Na(8)O6 octahedra, edges with two equivalent Fe(2)O6 octahedra, and edges with two equivalent Fe(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 17-18°. In the fifth Na site, Na(5) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(6) atoms to form distorted NaO6 octahedra that share corners with two equivalent Na(4)O6 octahedra, corners with two equivalent Fe(1)O6 octahedra, corners with two equivalent Fe(4)O6 octahedra,  an edgeedge with one Na(1)O6 octahedra,  an edgeedge with one Na(7)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, edges with two equivalent Na(8)O6 octahedra, edges with two equivalent Fe(1)O6 octahedra, and edges with two equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 11-17°. In the sixth Na site, Na(6) is bonded to two equivalent O(1), two equivalent O(4), and two equivalent O(5) atoms to form distorted NaO6 octahedra that share corners with two equivalent Na(3)O6 octahedra, corners with two equivalent Fe(2)O6 octahedra, corners with two equivalent Fe(3)O6 octahedra,  an edgeedge with one Na(2)O6 octahedra,  an edgeedge with one Na(8)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, edges with two equivalent Na(4)O6 octahedra, edges with two equivalent Na(7)O6 octahedra, edges with two equivalent Fe(3)O6 octahedra, and edges with two equivalent Fe(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 16-17°. In the seventh Na site, Na(7) is bonded to two equivalent O(2), two equivalent O(4), and two equivalent O(5) atoms to form distorted NaO6 octahedra that share corners with two equivalent Na(4)O6 octahedra, corners with two equivalent Fe(1)O6 octahedra, corners with two equivalent Fe(4)O6 octahedra,  an edgeedge with one Na(1)O6 octahedra,  an edgeedge with one Na(5)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, edges with two equivalent Na(6)O6 octahedra, edges with two equivalent Fe(3)O6 octahedra, and edges with two equivalent Fe(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 15-18°. In the eighth Na site, Na(8) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(6) atoms to form distorted NaO6 octahedra that share corners with two equivalent Na(3)O6 octahedra, corners with two equivalent Fe(2)O6 octahedra, corners with two equivalent Fe(3)O6 octahedra,  an edgeedge with one Na(2)O6 octahedra,  an edgeedge with one Na(6)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, edges with two equivalent Na(4)O6 octahedra, edges with two equivalent Na(5)O6 octahedra, edges with two equivalent Fe(1)O6 octahedra, and edges with two equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 11-17°. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(6) atoms to form FeO6 octahedra that share corners with two equivalent Na(1)O6 octahedra, corners with two equivalent Na(5)O6 octahedra, corners with two equivalent Na(7)O6 octahedra,  an edgeedge with one Na(4)O6 octahedra,  an edgeedge with one Fe(4)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, edges with two equivalent Na(5)O6 octahedra, edges with two equivalent Na(8)O6 octahedra, and edges with two equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 13-16°. In the second Fe site, Fe(2) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(6) atoms to form FeO6 octahedra that share corners with two equivalent Na(2)O6 octahedra, corners with two equivalent Na(6)O6 octahedra, corners with two equivalent Na(8)O6 octahedra,  an edgeedge with one Na(3)O6 octahedra,  an edgeedge with one Fe(3)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, edges with two equivalent Na(4)O6 octahedra, edges with two equivalent Na(5)O6 octahedra, edges with two equivalent Na(8)O6 octahedra, and edges with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 13-16°. In the third Fe site, Fe(3) is bonded to two equivalent O(1), two equivalent O(4), and two equivalent O(5) atoms to form FeO6 octahedra that share corners with two equivalent Na(2)O6 octahedra, corners with two equivalent Na(6)O6 octahedra, corners with two equivalent Na(8)O6 octahedra,  an edgeedge with one Na(3)O6 octahedra,  an edgeedge with one Fe(2)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, edges with two equivalent Na(4)O6 octahedra, edges with two equivalent Na(6)O6 octahedra, edges with two equivalent Na(7)O6 octahedra, and edges with two equivalent Fe(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 10-16°. In the fourth Fe site, Fe(4) is bonded to two equivalent O(2), two equivalent O(4), and two equivalent O(5) atoms to form FeO6 octahedra that share corners with two equivalent Na(1)O6 octahedra, corners with two equivalent Na(5)O6 octahedra, corners with two equivalent Na(7)O6 octahedra,  an edgeedge with one Na(4)O6 octahedra,  an edgeedge with one Fe(1)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, edges with two equivalent Na(6)O6 octahedra, edges with two equivalent Na(7)O6 octahedra, and edges with two equivalent Fe(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 11-15°. There are six inequivalent O sites. In the first O site, O(1) is bonded to one Na(1), one Na(4), one Na(6), one Na(8), one Fe(2), and one Fe(3) atom to form a mixture of distorted edge and corner-sharing ONa4Fe2 octahedra. The corner-sharing octahedral tilt angles range from 3-14°. In the second O site, O(2) is bonded to one Na(2), one Na(3), one Na(5), one Na(7), one Fe(1), and one Fe(4) atom to form a mixture of distorted edge and corner-sharing ONa4Fe2 octahedra. The corner-sharing octahedral tilt angles range from 4-14°. In the third O site, O(3) is bonded to one Na(1), one Na(4), one Na(5), one Na(8), one Fe(1), and one Fe(2) atom to form a mixture of distorted edge and corner-sharing ONa4Fe2 octahedra. The corner-sharing octahedral tilt angles range from 3-14°. In the fourth O site, O(4) is bonded to one Na(2), one Na(3), one Na(6), one Na(7), one Fe(3), and one Fe(4) atom to form a mixture of distorted edge and corner-sharing ONa4Fe2 octahedra. The corner-sharing octahedral tilt angles range from 3-13°. In the fifth O site, O(5) is bonded to one Na(1), one Na(4), one Na(6), one Na(7), one Fe(3), and one Fe(4) atom to form a mixture of distorted edge and corner-sharing ONa4Fe2 octahedra. The corner-sharing octahedral tilt angles range from 3-13°. In the sixth O site, O(6) is bonded to one Na(2), one Na(3), one Na(5), one Na(8), one Fe(1), and one Fe(2) atom to form a mixture of distorted edge and corner-sharing ONa4Fe2 octahedra. The corner-sharing octahedral tilt angles range from 3-14°.
Na2FeO3 is Caswellsilverite-like structured and crystallizes in the monoclinic P2 space group. There are eight inequivalent Na sites. In the first Na site, Na(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(5) atoms to form distorted NaO6 octahedra that share corners with two equivalent Na(4)O6 octahedra, corners with two equivalent Fe(1)O6 octahedra, corners with two equivalent Fe(4)O6 octahedra,  an edgeedge with one Na(5)O6 octahedra,  an edgeedge with one Na(7)O6 octahedra, edges with two equivalent Na(4)O6 octahedra, edges with two equivalent Na(6)O6 octahedra, edges with two equivalent Na(8)O6 octahedra, edges with two equivalent Fe(2)O6 octahedra, and edges with two equivalent Fe(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 11-17°. Both Na(1)-O(1) bond lengths are 2.26 Å. Both Na(1)-O(3) bond lengths are 2.47 Å. Both Na(1)-O(5) bond lengths are 2.54 Å. In the second Na site, Na(2) is bonded to two equivalent O(2), two equivalent O(4), and two equivalent O(6) atoms to form distorted NaO6 octahedra that share corners with two equivalent Na(3)O6 octahedra, corners with two equivalent Fe(2)O6 octahedra, corners with two equivalent Fe(3)O6 octahedra,  an edgeedge with one Na(6)O6 octahedra,  an edgeedge with one Na(8)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, edges with two equivalent Na(5)O6 octahedra, edges with two equivalent Na(7)O6 octahedra, edges with two equivalent Fe(1)O6 octahedra, and edges with two equivalent Fe(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 10-17°. Both Na(2)-O(2) bond lengths are 2.26 Å. Both Na(2)-O(4) bond lengths are 2.54 Å. Both Na(2)-O(6) bond lengths are 2.47 Å. In the third Na site, Na(3) is bonded to two equivalent O(2), two equivalent O(4), and two equivalent O(6) atoms to form NaO6 octahedra that share corners with two equivalent Na(2)O6 octahedra, corners with two equivalent Na(6)O6 octahedra, corners with two equivalent Na(8)O6 octahedra,  an edgeedge with one Fe(2)O6 octahedra,  an edgeedge with one Fe(3)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, edges with two equivalent Na(5)O6 octahedra, edges with two equivalent Na(7)O6 octahedra, edges with two equivalent Fe(1)O6 octahedra, and edges with two equivalent Fe(4)O6 octahedra. The corner-sharing octahedral tilt angles are 17°. Both Na(3)-O(2) bond lengths are 2.33 Å. Both Na(3)-O(4) bond lengths are 2.29 Å. Both Na(3)-O(6) bond lengths are 2.32 Å. In the fourth Na site, Na(4) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(5) atoms to form NaO6 octahedra that share corners with two equivalent Na(1)O6 octahedra, corners with two equivalent Na(5)O6 octahedra, corners with two equivalent Na(7)O6 octahedra,  an edgeedge with one Fe(1)O6 octahedra,  an edgeedge with one Fe(4)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, edges with two equivalent Na(6)O6 octahedra, edges with two equivalent Na(8)O6 octahedra, edges with two equivalent Fe(2)O6 octahedra, and edges with two equivalent Fe(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 17-18°. Both Na(4)-O(1) bond lengths are 2.33 Å. Both Na(4)-O(3) bond lengths are 2.32 Å. Both Na(4)-O(5) bond lengths are 2.29 Å. In the fifth Na site, Na(5) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(6) atoms to form distorted NaO6 octahedra that share corners with two equivalent Na(4)O6 octahedra, corners with two equivalent Fe(1)O6 octahedra, corners with two equivalent Fe(4)O6 octahedra,  an edgeedge with one Na(1)O6 octahedra,  an edgeedge with one Na(7)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, edges with two equivalent Na(8)O6 octahedra, edges with two equivalent Fe(1)O6 octahedra, and edges with two equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 11-17°. Both Na(5)-O(2) bond lengths are 2.48 Å. Both Na(5)-O(3) bond lengths are 2.27 Å. Both Na(5)-O(6) bond lengths are 2.59 Å. In the sixth Na site, Na(6) is bonded to two equivalent O(1), two equivalent O(4), and two equivalent O(5) atoms to form distorted NaO6 octahedra that share corners with two equivalent Na(3)O6 octahedra, corners with two equivalent Fe(2)O6 octahedra, corners with two equivalent Fe(3)O6 octahedra,  an edgeedge with one Na(2)O6 octahedra,  an edgeedge with one Na(8)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, edges with two equivalent Na(4)O6 octahedra, edges with two equivalent Na(7)O6 octahedra, edges with two equivalent Fe(3)O6 octahedra, and edges with two equivalent Fe(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 16-17°. Both Na(6)-O(1) bond lengths are 2.41 Å. Both Na(6)-O(4) bond lengths are 2.27 Å. Both Na(6)-O(5) bond lengths are 2.51 Å. In the seventh Na site, Na(7) is bonded to two equivalent O(2), two equivalent O(4), and two equivalent O(5) atoms to form distorted NaO6 octahedra that share corners with two equivalent Na(4)O6 octahedra, corners with two equivalent Fe(1)O6 octahedra, corners with two equivalent Fe(4)O6 octahedra,  an edgeedge with one Na(1)O6 octahedra,  an edgeedge with one Na(5)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, edges with two equivalent Na(6)O6 octahedra, edges with two equivalent Fe(3)O6 octahedra, and edges with two equivalent Fe(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 15-18°. Both Na(7)-O(2) bond lengths are 2.42 Å. Both Na(7)-O(4) bond lengths are 2.49 Å. Both Na(7)-O(5) bond lengths are 2.28 Å. In the eighth Na site, Na(8) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(6) atoms to form distorted NaO6 octahedra that share corners with two equivalent Na(3)O6 octahedra, corners with two equivalent Fe(2)O6 octahedra, corners with two equivalent Fe(3)O6 octahedra,  an edgeedge with one Na(2)O6 octahedra,  an edgeedge with one Na(6)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, edges with two equivalent Na(4)O6 octahedra, edges with two equivalent Na(5)O6 octahedra, edges with two equivalent Fe(1)O6 octahedra, and edges with two equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 11-17°. Both Na(8)-O(1) bond lengths are 2.48 Å. Both Na(8)-O(3) bond lengths are 2.58 Å. Both Na(8)-O(6) bond lengths are 2.27 Å. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(6) atoms to form FeO6 octahedra that share corners with two equivalent Na(1)O6 octahedra, corners with two equivalent Na(5)O6 octahedra, corners with two equivalent Na(7)O6 octahedra,  an edgeedge with one Na(4)O6 octahedra,  an edgeedge with one Fe(4)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, edges with two equivalent Na(5)O6 octahedra, edges with two equivalent Na(8)O6 octahedra, and edges with two equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 13-16°. Both Fe(1)-O(2) bond lengths are 2.08 Å. Both Fe(1)-O(3) bond lengths are 2.05 Å. Both Fe(1)-O(6) bond lengths are 1.97 Å. In the second Fe site, Fe(2) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(6) atoms to form FeO6 octahedra that share corners with two equivalent Na(2)O6 octahedra, corners with two equivalent Na(6)O6 octahedra, corners with two equivalent Na(8)O6 octahedra,  an edgeedge with one Na(3)O6 octahedra,  an edgeedge with one Fe(3)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, edges with two equivalent Na(4)O6 octahedra, edges with two equivalent Na(5)O6 octahedra, edges with two equivalent Na(8)O6 octahedra, and edges with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 13-16°. Both Fe(2)-O(1) bond lengths are 2.07 Å. Both Fe(2)-O(3) bond lengths are 1.98 Å. Both Fe(2)-O(6) bond lengths are 2.05 Å. In the third Fe site, Fe(3) is bonded to two equivalent O(1), two equivalent O(4), and two equivalent O(5) atoms to form FeO6 octahedra that share corners with two equivalent Na(2)O6 octahedra, corners with two equivalent Na(6)O6 octahedra, corners with two equivalent Na(8)O6 octahedra,  an edgeedge with one Na(3)O6 octahedra,  an edgeedge with one Fe(2)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, edges with two equivalent Na(4)O6 octahedra, edges with two equivalent Na(6)O6 octahedra, edges with two equivalent Na(7)O6 octahedra, and edges with two equivalent Fe(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 10-16°. Both Fe(3)-O(1) bond lengths are 1.96 Å. Both Fe(3)-O(4) bond lengths are 1.95 Å. Both Fe(3)-O(5) bond lengths are 2.07 Å. In the fourth Fe site, Fe(4) is bonded to two equivalent O(2), two equivalent O(4), and two equivalent O(5) atoms to form FeO6 octahedra that share corners with two equivalent Na(1)O6 octahedra, corners with two equivalent Na(5)O6 octahedra, corners with two equivalent Na(7)O6 octahedra,  an edgeedge with one Na(4)O6 octahedra,  an edgeedge with one Fe(1)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, edges with two equivalent Na(6)O6 octahedra, edges with two equivalent Na(7)O6 octahedra, and edges with two equivalent Fe(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 11-15°. Both Fe(4)-O(2) bond lengths are 1.95 Å. Both Fe(4)-O(4) bond lengths are 2.09 Å. Both Fe(4)-O(5) bond lengths are 1.95 Å. There are six inequivalent O sites. In the first O site, O(1) is bonded to one Na(1), one Na(4), one Na(6), one Na(8), one Fe(2), and one Fe(3) atom to form a mixture of distorted edge and corner-sharing ONa4Fe2 octahedra. The corner-sharing octahedral tilt angles range from 3-14°. In the second O site, O(2) is bonded to one Na(2), one Na(3), one Na(5), one Na(7), one Fe(1), and one Fe(4) atom to form a mixture of distorted edge and corner-sharing ONa4Fe2 octahedra. The corner-sharing octahedral tilt angles range from 4-14°. In the third O site, O(3) is bonded to one Na(1), one Na(4), one Na(5), one Na(8), one Fe(1), and one Fe(2) atom to form a mixture of distorted edge and corner-sharing ONa4Fe2 octahedra. The corner-sharing octahedral tilt angles range from 3-14°. In the fourth O site, O(4) is bonded to one Na(2), one Na(3), one Na(6), one Na(7), one Fe(3), and one Fe(4) atom to form a mixture of distorted edge and corner-sharing ONa4Fe2 octahedra. The corner-sharing octahedral tilt angles range from 3-13°. In the fifth O site, O(5) is bonded to one Na(1), one Na(4), one Na(6), one Na(7), one Fe(3), and one Fe(4) atom to form a mixture of distorted edge and corner-sharing ONa4Fe2 octahedra. The corner-sharing octahedral tilt angles range from 3-13°. In the sixth O site, O(6) is bonded to one Na(2), one Na(3), one Na(5), one Na(8), one Fe(1), and one Fe(2) atom to form a mixture of distorted edge and corner-sharing ONa4Fe2 octahedra. The corner-sharing octahedral tilt angles range from 3-14°.