Na3BaCPO7 crystallizes in the monoclinic P2_1/m space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 6-coordinate geometry to one O(2), one O(3), two equivalent O(1), and two equivalent O(4) atoms. In the second Na site, Na(2) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom. Ba(1) is bonded to one O(2), one O(3), one O(5), two equivalent O(4), and two equivalent O(6) atoms to form distorted BaO7 pentagonal bipyramids that share corners with two equivalent Ba(1)O7 pentagonal bipyramids, corners with three equivalent P(1)O4 tetrahedra, and  an edgeedge with one P(1)O4 tetrahedra. C(1) is bonded in a trigonal planar geometry to one O(1), one O(2), and one O(3) atom. P(1) is bonded to one O(5), one O(6), and two equivalent O(4) atoms to form PO4 tetrahedra that share corners with three equivalent Ba(1)O7 pentagonal bipyramids and  an edgeedge with one Ba(1)O7 pentagonal bipyramid. There are six inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to two equivalent Na(1), two equivalent Na(2), and one C(1) atom. In the second O site, O(2) is bonded in a 5-coordinate geometry to one Na(1), two equivalent Na(2), one Ba(1), and one C(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Na(1), two equivalent Na(2), one Ba(1), and one C(1) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Na(1), one Na(2), one Ba(1), and one P(1) atom. In the fifth O site, O(5) is bonded in a distorted tetrahedral geometry to two equivalent Na(2), one Ba(1), and one P(1) atom. In the sixth O site, O(6) is bonded in a distorted single-bond geometry to two equivalent Na(2), two equivalent Ba(1), and one P(1) atom.
Na3BaCPO7 crystallizes in the monoclinic P2_1/m space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 6-coordinate geometry to one O(2), one O(3), two equivalent O(1), and two equivalent O(4) atoms. The Na(1)-O(2) bond length is 2.38 Å. The Na(1)-O(3) bond length is 2.51 Å. There is one shorter (2.54 Å) and one longer (2.85 Å) Na(1)-O(1) bond length. Both Na(1)-O(4) bond lengths are 2.66 Å. In the second Na site, Na(2) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom. The Na(2)-O(1) bond length is 2.34 Å. The Na(2)-O(2) bond length is 2.94 Å. The Na(2)-O(3) bond length is 2.88 Å. The Na(2)-O(4) bond length is 2.41 Å. The Na(2)-O(5) bond length is 2.34 Å. The Na(2)-O(6) bond length is 2.86 Å. Ba(1) is bonded to one O(2), one O(3), one O(5), two equivalent O(4), and two equivalent O(6) atoms to form distorted BaO7 pentagonal bipyramids that share corners with two equivalent Ba(1)O7 pentagonal bipyramids, corners with three equivalent P(1)O4 tetrahedra, and  an edgeedge with one P(1)O4 tetrahedra. The Ba(1)-O(2) bond length is 2.82 Å. The Ba(1)-O(3) bond length is 2.76 Å. The Ba(1)-O(5) bond length is 2.63 Å. Both Ba(1)-O(4) bond lengths are 2.64 Å. There is one shorter (2.73 Å) and one longer (2.85 Å) Ba(1)-O(6) bond length. C(1) is bonded in a trigonal planar geometry to one O(1), one O(2), and one O(3) atom. The C(1)-O(1) bond length is 1.30 Å. The C(1)-O(2) bond length is 1.31 Å. The C(1)-O(3) bond length is 1.31 Å. P(1) is bonded to one O(5), one O(6), and two equivalent O(4) atoms to form PO4 tetrahedra that share corners with three equivalent Ba(1)O7 pentagonal bipyramids and  an edgeedge with one Ba(1)O7 pentagonal bipyramid. The P(1)-O(5) bond length is 1.56 Å. The P(1)-O(6) bond length is 1.57 Å. Both P(1)-O(4) bond lengths are 1.56 Å. There are six inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to two equivalent Na(1), two equivalent Na(2), and one C(1) atom. In the second O site, O(2) is bonded in a 5-coordinate geometry to one Na(1), two equivalent Na(2), one Ba(1), and one C(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Na(1), two equivalent Na(2), one Ba(1), and one C(1) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Na(1), one Na(2), one Ba(1), and one P(1) atom. In the fifth O site, O(5) is bonded in a distorted tetrahedral geometry to two equivalent Na(2), one Ba(1), and one P(1) atom. In the sixth O site, O(6) is bonded in a distorted single-bond geometry to two equivalent Na(2), two equivalent Ba(1), and one P(1) atom.