Ba3(InP2)2 crystallizes in the monoclinic C2/c space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to two equivalent P(2) and four equivalent P(1) atoms to form distorted BaP6 octahedra that share corners with four equivalent In(1)P4 tetrahedra, edges with two equivalent Ba(1)P6 octahedra, and edges with four equivalent In(1)P4 tetrahedra. In the second Ba site, Ba(2) is bonded in a 6-coordinate geometry to two equivalent P(1) and four equivalent P(2) atoms. In(1) is bonded to two equivalent P(1) and two equivalent P(2) atoms to form distorted InP4 tetrahedra that share corners with two equivalent Ba(1)P6 octahedra, corners with two equivalent In(1)P4 tetrahedra, edges with two equivalent Ba(1)P6 octahedra, and  an edgeedge with one In(1)P4 tetrahedra. The corner-sharing octahedral tilt angles range from 32-56°. There are two inequivalent P sites. In the first P site, P(1) is bonded to two equivalent Ba(1), two equivalent Ba(2), and two equivalent In(1) atoms to form a mixture of distorted edge and corner-sharing PBa4In2 pentagonal pyramids. In the second P site, P(2) is bonded in a 7-coordinate geometry to one Ba(1), four equivalent Ba(2), and two equivalent In(1) atoms.
Ba3(InP2)2 crystallizes in the monoclinic C2/c space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to two equivalent P(2) and four equivalent P(1) atoms to form distorted BaP6 octahedra that share corners with four equivalent In(1)P4 tetrahedra, edges with two equivalent Ba(1)P6 octahedra, and edges with four equivalent In(1)P4 tetrahedra. Both Ba(1)-P(2) bond lengths are 3.38 Å. There are two shorter (3.19 Å) and two longer (3.28 Å) Ba(1)-P(1) bond lengths. In the second Ba site, Ba(2) is bonded in a 6-coordinate geometry to two equivalent P(1) and four equivalent P(2) atoms. There is one shorter (3.18 Å) and one longer (3.24 Å) Ba(2)-P(1) bond length. There are a spread of Ba(2)-P(2) bond distances ranging from 3.34-3.74 Å. In(1) is bonded to two equivalent P(1) and two equivalent P(2) atoms to form distorted InP4 tetrahedra that share corners with two equivalent Ba(1)P6 octahedra, corners with two equivalent In(1)P4 tetrahedra, edges with two equivalent Ba(1)P6 octahedra, and  an edgeedge with one In(1)P4 tetrahedra. The corner-sharing octahedral tilt angles range from 32-56°. There is one shorter (2.58 Å) and one longer (2.60 Å) In(1)-P(1) bond length. There is one shorter (2.62 Å) and one longer (2.65 Å) In(1)-P(2) bond length. There are two inequivalent P sites. In the first P site, P(1) is bonded to two equivalent Ba(1), two equivalent Ba(2), and two equivalent In(1) atoms to form a mixture of distorted edge and corner-sharing PBa4In2 pentagonal pyramids. In the second P site, P(2) is bonded in a 7-coordinate geometry to one Ba(1), four equivalent Ba(2), and two equivalent In(1) atoms.