BaCo2(PO4)2 crystallizes in the triclinic P-1 space group. Ba(1) is bonded to two equivalent O(1), two equivalent O(3), two equivalent O(4), and six equivalent O(2) atoms to form distorted BaO12 cuboctahedra that share corners with six equivalent Co(1)O6 octahedra, edges with six equivalent Ba(1)O12 cuboctahedra, edges with six equivalent P(1)O4 tetrahedra, and faces with two equivalent Co(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 48-50°. Co(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form CoO6 octahedra that share corners with three equivalent Ba(1)O12 cuboctahedra, corners with six equivalent P(1)O4 tetrahedra, edges with three equivalent Co(1)O6 octahedra, and  a faceface with one Ba(1)O12 cuboctahedra. 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 six equivalent Co(1)O6 octahedra and edges with three equivalent Ba(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 48-55°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Ba(1), two equivalent Co(1), and one P(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to three equivalent Ba(1) and one P(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Ba(1), two equivalent Co(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Ba(1), two equivalent Co(1), and one P(1) atom.
BaCo2(PO4)2 crystallizes in the triclinic P-1 space group. Ba(1) is bonded to two equivalent O(1), two equivalent O(3), two equivalent O(4), and six equivalent O(2) atoms to form distorted BaO12 cuboctahedra that share corners with six equivalent Co(1)O6 octahedra, edges with six equivalent Ba(1)O12 cuboctahedra, edges with six equivalent P(1)O4 tetrahedra, and faces with two equivalent Co(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 48-50°. Both Ba(1)-O(1) bond lengths are 3.18 Å. Both Ba(1)-O(3) bond lengths are 3.30 Å. Both Ba(1)-O(4) bond lengths are 3.22 Å. There are a spread of Ba(1)-O(2) bond distances ranging from 2.86-2.92 Å. Co(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form CoO6 octahedra that share corners with three equivalent Ba(1)O12 cuboctahedra, corners with six equivalent P(1)O4 tetrahedra, edges with three equivalent Co(1)O6 octahedra, and  a faceface with one Ba(1)O12 cuboctahedra. There is one shorter (2.08 Å) and one longer (2.09 Å) Co(1)-O(1) bond length. There is one shorter (2.13 Å) and one longer (2.14 Å) Co(1)-O(3) bond length. There is one shorter (2.08 Å) and one longer (2.09 Å) Co(1)-O(4) bond length. 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 six equivalent Co(1)O6 octahedra and edges with three equivalent Ba(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 48-55°. The P(1)-O(1) bond length is 1.57 Å. The P(1)-O(2) bond length is 1.53 Å. The P(1)-O(3) bond length is 1.56 Å. The P(1)-O(4) bond length is 1.57 Å. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Ba(1), two equivalent Co(1), and one P(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to three equivalent Ba(1) and one P(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Ba(1), two equivalent Co(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Ba(1), two equivalent Co(1), and one P(1) atom.