Na4ZnGa(PO4)3 crystallizes in the trigonal R3c space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms. In the second Na site, Na(2) is bonded in a distorted hexagonal planar geometry to three equivalent O(3) and three equivalent O(4) atoms. Zn(1) is bonded to three equivalent O(1) and three equivalent O(3) atoms to form distorted ZnO6 octahedra that share corners with six equivalent P(1)O4 tetrahedra. Ga(1) is bonded to three equivalent O(2) and three equivalent O(4) atoms to form GaO6 octahedra that share corners with six equivalent P(1)O4 tetrahedra. P(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form PO4 tetrahedra that share corners with two equivalent Zn(1)O6 octahedra and corners with two equivalent Ga(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 30-40°. There are four inequivalent O sites. In the first O site, O(3) is bonded to one Na(2), two equivalent Na(1), one Zn(1), and one P(1) atom to form distorted ONa3ZnP trigonal bipyramids that share corners with six equivalent O(4)Na3GaP trigonal bipyramids,  an edgeedge with one O(4)Na3GaP trigonal bipyramid, and faces with two equivalent O(3)Na3ZnP trigonal bipyramids. In the second O site, O(4) is bonded to one Na(2), two equivalent Na(1), one Ga(1), and one P(1) atom to form distorted ONa3GaP trigonal bipyramids that share corners with six equivalent O(3)Na3ZnP trigonal bipyramids,  an edgeedge with one O(3)Na3ZnP trigonal bipyramid, and faces with two equivalent O(4)Na3GaP trigonal bipyramids. In the third O site, O(1) is bonded in a 3-coordinate geometry to two equivalent Na(1), one Zn(1), and one P(1) atom. In the fourth O site, O(2) is bonded in a 2-coordinate geometry to two equivalent Na(1), one Ga(1), and one P(1) atom.
Na4ZnGa(PO4)3 crystallizes in the trigonal R3c space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms. There is one shorter (2.42 Å) and one longer (3.01 Å) Na(1)-O(1) bond length. There is one shorter (2.68 Å) and one longer (2.88 Å) Na(1)-O(2) bond length. There is one shorter (2.37 Å) and one longer (2.51 Å) Na(1)-O(3) bond length. There is one shorter (2.47 Å) and one longer (2.60 Å) Na(1)-O(4) bond length. In the second Na site, Na(2) is bonded in a distorted hexagonal planar geometry to three equivalent O(3) and three equivalent O(4) atoms. All Na(2)-O(3) bond lengths are 2.47 Å. All Na(2)-O(4) bond lengths are 2.48 Å. Zn(1) is bonded to three equivalent O(1) and three equivalent O(3) atoms to form distorted ZnO6 octahedra that share corners with six equivalent P(1)O4 tetrahedra. All Zn(1)-O(1) bond lengths are 2.00 Å. All Zn(1)-O(3) bond lengths are 2.21 Å. Ga(1) is bonded to three equivalent O(2) and three equivalent O(4) atoms to form GaO6 octahedra that share corners with six equivalent P(1)O4 tetrahedra. All Ga(1)-O(2) bond lengths are 1.99 Å. All Ga(1)-O(4) bond lengths are 2.07 Å. P(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form PO4 tetrahedra that share corners with two equivalent Zn(1)O6 octahedra and corners with two equivalent Ga(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 30-40°. The P(1)-O(1) bond length is 1.53 Å. The P(1)-O(2) bond length is 1.57 Å. The P(1)-O(3) bond length is 1.54 Å. The P(1)-O(4) bond length is 1.58 Å. There are four inequivalent O sites. In the first O site, O(3) is bonded to one Na(2), two equivalent Na(1), one Zn(1), and one P(1) atom to form distorted ONa3ZnP trigonal bipyramids that share corners with six equivalent O(4)Na3GaP trigonal bipyramids,  an edgeedge with one O(4)Na3GaP trigonal bipyramid, and faces with two equivalent O(3)Na3ZnP trigonal bipyramids. In the second O site, O(4) is bonded to one Na(2), two equivalent Na(1), one Ga(1), and one P(1) atom to form distorted ONa3GaP trigonal bipyramids that share corners with six equivalent O(3)Na3ZnP trigonal bipyramids,  an edgeedge with one O(3)Na3ZnP trigonal bipyramid, and faces with two equivalent O(4)Na3GaP trigonal bipyramids. In the third O site, O(1) is bonded in a 3-coordinate geometry to two equivalent Na(1), one Zn(1), and one P(1) atom. In the fourth O site, O(2) is bonded in a 2-coordinate geometry to two equivalent Na(1), one Ga(1), and one P(1) atom.