Na3PO4 is Enargite structured and crystallizes in the orthorhombic Pmn2_1 space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form NaO4 tetrahedra that share corners with four equivalent Na(1)O4 tetrahedra, corners with four equivalent Na(2)O4 tetrahedra, and corners with four equivalent P(1)O4 tetrahedra. In the second Na site, Na(2) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form NaO4 tetrahedra that share corners with four equivalent P(1)O4 tetrahedra and corners with eight equivalent Na(1)O4 tetrahedra. P(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form PO4 tetrahedra that share corners with four equivalent Na(2)O4 tetrahedra and corners with eight equivalent Na(1)O4 tetrahedra. There are three inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to one Na(2), two equivalent Na(1), and one P(1) atom. In the second O site, O(2) is bonded in a distorted trigonal pyramidal geometry to one Na(2), two equivalent Na(1), and one P(1) atom. In the third O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to one Na(2), two equivalent Na(1), and one P(1) atom.
Na3PO4 is Enargite structured and crystallizes in the orthorhombic Pmn2_1 space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form NaO4 tetrahedra that share corners with four equivalent Na(1)O4 tetrahedra, corners with four equivalent Na(2)O4 tetrahedra, and corners with four equivalent P(1)O4 tetrahedra. The Na(1)-O(1) bond length is 2.26 Å. The Na(1)-O(2) bond length is 2.21 Å. There is one shorter (2.27 Å) and one longer (2.28 Å) Na(1)-O(3) bond length. In the second Na site, Na(2) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form NaO4 tetrahedra that share corners with four equivalent P(1)O4 tetrahedra and corners with eight equivalent Na(1)O4 tetrahedra. The Na(2)-O(1) bond length is 2.31 Å. The Na(2)-O(2) bond length is 2.25 Å. Both Na(2)-O(3) bond lengths are 2.36 Å. P(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form PO4 tetrahedra that share corners with four equivalent Na(2)O4 tetrahedra and corners with eight equivalent Na(1)O4 tetrahedra. The P(1)-O(1) bond length is 1.55 Å. The P(1)-O(2) bond length is 1.54 Å. Both P(1)-O(3) bond lengths are 1.55 Å. There are three inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to one Na(2), two equivalent Na(1), and one P(1) atom. In the second O site, O(2) is bonded in a distorted trigonal pyramidal geometry to one Na(2), two equivalent Na(1), and one P(1) atom. In the third O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to one Na(2), two equivalent Na(1), and one P(1) atom.