Na2CrO4 crystallizes in the triclinic P-1 space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 5-coordinate geometry to one O(2), one O(3), one O(4), and two equivalent O(1) atoms. In the second Na site, Na(2) is bonded to one O(2), two equivalent O(3), and two equivalent O(4) atoms to form distorted NaO5 square pyramids that share corners with three equivalent Cr(1)O4 tetrahedra, edges with two equivalent Na(2)O5 square pyramids, and  an edgeedge with one Cr(1)O4 tetrahedra. Cr(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form CrO4 tetrahedra that share corners with three equivalent Na(2)O5 square pyramids and  an edgeedge with one Na(2)O5 square pyramid. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal non-coplanar geometry to two equivalent Na(1) and one Cr(1) atom. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Na(1), one Na(2), and one Cr(1) atom. In the third O site, O(3) is bonded in a distorted see-saw-like geometry to one Na(1), two equivalent Na(2), and one Cr(1) atom. In the fourth O site, O(4) is bonded in a distorted rectangular see-saw-like geometry to one Na(1), two equivalent Na(2), and one Cr(1) atom.
Na2CrO4 crystallizes in the triclinic P-1 space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 5-coordinate geometry to one O(2), one O(3), one O(4), and two equivalent O(1) atoms. The Na(1)-O(2) bond length is 2.33 Å. The Na(1)-O(3) bond length is 2.60 Å. The Na(1)-O(4) bond length is 2.47 Å. There is one shorter (2.34 Å) and one longer (2.56 Å) Na(1)-O(1) bond length. In the second Na site, Na(2) is bonded to one O(2), two equivalent O(3), and two equivalent O(4) atoms to form distorted NaO5 square pyramids that share corners with three equivalent Cr(1)O4 tetrahedra, edges with two equivalent Na(2)O5 square pyramids, and  an edgeedge with one Cr(1)O4 tetrahedra. The Na(2)-O(2) bond length is 2.50 Å. There is one shorter (2.30 Å) and one longer (2.43 Å) Na(2)-O(3) bond length. There is one shorter (2.34 Å) and one longer (2.36 Å) Na(2)-O(4) bond length. Cr(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form CrO4 tetrahedra that share corners with three equivalent Na(2)O5 square pyramids and  an edgeedge with one Na(2)O5 square pyramid. The Cr(1)-O(1) bond length is 1.65 Å. The Cr(1)-O(2) bond length is 1.66 Å. The Cr(1)-O(3) bond length is 1.67 Å. The Cr(1)-O(4) bond length is 1.68 Å. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal non-coplanar geometry to two equivalent Na(1) and one Cr(1) atom. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Na(1), one Na(2), and one Cr(1) atom. In the third O site, O(3) is bonded in a distorted see-saw-like geometry to one Na(1), two equivalent Na(2), and one Cr(1) atom. In the fourth O site, O(4) is bonded in a distorted rectangular see-saw-like geometry to one Na(1), two equivalent Na(2), and one Cr(1) atom.