Ba(Ni5P3)2 crystallizes in the orthorhombic Cmce space group. Ba(1) is bonded in a 18-coordinate geometry to four equivalent Ni(4), six equivalent Ni(3), two equivalent P(2), two equivalent P(3), and four equivalent P(1) atoms. There are four inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a 4-coordinate geometry to two equivalent P(1) and two equivalent P(3) atoms. In the second Ni site, Ni(2) is bonded in a 4-coordinate geometry to two equivalent P(2) and two equivalent P(3) atoms. In the third Ni site, Ni(3) is bonded to three equivalent Ba(1), two equivalent P(1), and two equivalent P(2) atoms to form distorted NiBa3P4 tetrahedra that share corners with six equivalent Ni(4)BaP4 tetrahedra, corners with nine equivalent Ni(3)Ba3P4 tetrahedra, edges with four equivalent Ni(4)BaP4 tetrahedra, faces with two equivalent Ni(4)BaP4 tetrahedra, and faces with three equivalent Ni(3)Ba3P4 tetrahedra. In the fourth Ni site, Ni(4) is bonded to one Ba(1), one P(1), one P(2), and two equivalent P(3) atoms to form distorted NiBaP4 tetrahedra that share corners with three equivalent Ni(3)Ba3P4 tetrahedra, corners with five equivalent Ni(4)BaP4 tetrahedra, edges with two equivalent Ni(3)Ba3P4 tetrahedra, edges with three equivalent Ni(4)BaP4 tetrahedra, and  a faceface with one Ni(3)Ba3P4 tetrahedra. There are three inequivalent P sites. In the first P site, P(1) is bonded in a 8-coordinate geometry to two equivalent Ba(1), two equivalent Ni(1), two equivalent Ni(3), and two equivalent Ni(4) atoms. In the second P site, P(2) is bonded in a 6-coordinate geometry to one Ba(1), two equivalent Ni(2), two equivalent Ni(3), and two equivalent Ni(4) atoms. In the third P site, P(3) is bonded in a 8-coordinate geometry to one Ba(1), two equivalent Ni(1), two equivalent Ni(2), and four equivalent Ni(4) atoms.
Ba(Ni5P3)2 crystallizes in the orthorhombic Cmce space group. Ba(1) is bonded in a 18-coordinate geometry to four equivalent Ni(4), six equivalent Ni(3), two equivalent P(2), two equivalent P(3), and four equivalent P(1) atoms. All Ba(1)-Ni(4) bond lengths are 3.44 Å. There are two shorter (3.43 Å) and four longer (3.46 Å) Ba(1)-Ni(3) bond lengths. Both Ba(1)-P(2) bond lengths are 3.58 Å. Both Ba(1)-P(3) bond lengths are 3.45 Å. All Ba(1)-P(1) bond lengths are 3.25 Å. There are four inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a 4-coordinate geometry to two equivalent P(1) and two equivalent P(3) atoms. Both Ni(1)-P(1) bond lengths are 2.31 Å. There is one shorter (2.34 Å) and one longer (2.47 Å) Ni(1)-P(3) bond length. In the second Ni site, Ni(2) is bonded in a 4-coordinate geometry to two equivalent P(2) and two equivalent P(3) atoms. Both Ni(2)-P(2) bond lengths are 2.26 Å. Both Ni(2)-P(3) bond lengths are 2.35 Å. In the third Ni site, Ni(3) is bonded to three equivalent Ba(1), two equivalent P(1), and two equivalent P(2) atoms to form distorted NiBa3P4 tetrahedra that share corners with six equivalent Ni(4)BaP4 tetrahedra, corners with nine equivalent Ni(3)Ba3P4 tetrahedra, edges with four equivalent Ni(4)BaP4 tetrahedra, faces with two equivalent Ni(4)BaP4 tetrahedra, and faces with three equivalent Ni(3)Ba3P4 tetrahedra. Both Ni(3)-P(1) bond lengths are 2.24 Å. There is one shorter (2.19 Å) and one longer (2.27 Å) Ni(3)-P(2) bond length. In the fourth Ni site, Ni(4) is bonded to one Ba(1), one P(1), one P(2), and two equivalent P(3) atoms to form distorted NiBaP4 tetrahedra that share corners with three equivalent Ni(3)Ba3P4 tetrahedra, corners with five equivalent Ni(4)BaP4 tetrahedra, edges with two equivalent Ni(3)Ba3P4 tetrahedra, edges with three equivalent Ni(4)BaP4 tetrahedra, and  a faceface with one Ni(3)Ba3P4 tetrahedra. The Ni(4)-P(1) bond length is 2.24 Å. The Ni(4)-P(2) bond length is 2.33 Å. There is one shorter (2.21 Å) and one longer (2.32 Å) Ni(4)-P(3) bond length. There are three inequivalent P sites. In the first P site, P(1) is bonded in a 8-coordinate geometry to two equivalent Ba(1), two equivalent Ni(1), two equivalent Ni(3), and two equivalent Ni(4) atoms. In the second P site, P(2) is bonded in a 6-coordinate geometry to one Ba(1), two equivalent Ni(2), two equivalent Ni(3), and two equivalent Ni(4) atoms. In the third P site, P(3) is bonded in a 8-coordinate geometry to one Ba(1), two equivalent Ni(1), two equivalent Ni(2), and four equivalent Ni(4) atoms.