Ca2Ni10H crystallizes in the orthorhombic Amm2 space group. Ca(1) is bonded in a distorted single-bond geometry to two equivalent Ni(3), two equivalent Ni(5), three equivalent Ni(1), three equivalent Ni(2), four equivalent Ni(6), and one H(1) atom. There are six inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a 12-coordinate geometry to three equivalent Ca(1), one Ni(3), one Ni(5), two equivalent Ni(4), two equivalent Ni(6), and three equivalent Ni(2) atoms. In the second Ni site, Ni(2) is bonded in a 9-coordinate geometry to three equivalent Ca(1), one Ni(3), one Ni(5), two equivalent Ni(4), two equivalent Ni(6), and three equivalent Ni(1) atoms. In the third Ni site, Ni(3) is bonded to four equivalent Ca(1), two equivalent Ni(1), two equivalent Ni(2), and four equivalent Ni(4) atoms to form distorted NiCa4Ni8 cuboctahedra that share corners with four equivalent Ni(3)Ca4Ni8 cuboctahedra, corners with four equivalent Ni(5)Ca4Ni8 cuboctahedra, corners with eight equivalent Ni(6)Ca4Ni8 cuboctahedra, edges with two equivalent Ni(3)Ca4Ni8 cuboctahedra, edges with eight equivalent Ni(6)Ca4Ni8 cuboctahedra,  an edgeedge with one H(1)Ca2Ni2 tetrahedra, faces with two equivalent Ni(5)Ca4Ni8 cuboctahedra, and faces with two equivalent H(1)Ca2Ni2 tetrahedra. In the fourth Ni site, Ni(4) is bonded in a single-bond geometry to two equivalent Ni(1), two equivalent Ni(2), two equivalent Ni(3), and one H(1) atom. In the fifth Ni site, Ni(5) is bonded to four equivalent Ca(1), two equivalent Ni(1), two equivalent Ni(2), and four equivalent Ni(6) atoms to form NiCa4Ni8 cuboctahedra that share corners with four equivalent Ni(3)Ca4Ni8 cuboctahedra, corners with four equivalent Ni(5)Ca4Ni8 cuboctahedra, corners with four equivalent H(1)Ca2Ni2 tetrahedra, edges with two equivalent Ni(5)Ca4Ni8 cuboctahedra, faces with two equivalent Ni(3)Ca4Ni8 cuboctahedra, and faces with eight equivalent Ni(6)Ca4Ni8 cuboctahedra. In the sixth Ni site, Ni(6) is bonded to four equivalent Ca(1), two equivalent Ni(1), two equivalent Ni(2), two equivalent Ni(5), and two equivalent Ni(6) atoms to form NiCa4Ni8 cuboctahedra that share corners with four equivalent Ni(3)Ca4Ni8 cuboctahedra, corners with four equivalent Ni(6)Ca4Ni8 cuboctahedra, corners with four equivalent H(1)Ca2Ni2 tetrahedra, edges with two equivalent Ni(6)Ca4Ni8 cuboctahedra, edges with four equivalent Ni(3)Ca4Ni8 cuboctahedra, faces with four equivalent Ni(5)Ca4Ni8 cuboctahedra, and faces with four equivalent Ni(6)Ca4Ni8 cuboctahedra. H(1) is bonded to two equivalent Ca(1) and two equivalent Ni(4) atoms to form HCa2Ni2 tetrahedra that share corners with four equivalent Ni(5)Ca4Ni8 cuboctahedra, corners with eight equivalent Ni(6)Ca4Ni8 cuboctahedra,  an edgeedge with one Ni(3)Ca4Ni8 cuboctahedra, and faces with two equivalent Ni(3)Ca4Ni8 cuboctahedra.
Ca2Ni10H crystallizes in the orthorhombic Amm2 space group. Ca(1) is bonded in a distorted single-bond geometry to two equivalent Ni(3), two equivalent Ni(5), three equivalent Ni(1), three equivalent Ni(2), four equivalent Ni(6), and one H(1) atom. Both Ca(1)-Ni(3) bond lengths are 3.20 Å. Both Ca(1)-Ni(5) bond lengths are 3.12 Å. There are two shorter (2.84 Å) and one longer (2.87 Å) Ca(1)-Ni(1) bond length. All Ca(1)-Ni(2) bond lengths are 2.85 Å. All Ca(1)-Ni(6) bond lengths are 3.11 Å. The Ca(1)-H(1) bond length is 2.36 Å. There are six inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a 12-coordinate geometry to three equivalent Ca(1), one Ni(3), one Ni(5), two equivalent Ni(4), two equivalent Ni(6), and three equivalent Ni(2) atoms. The Ni(1)-Ni(3) bond length is 2.41 Å. The Ni(1)-Ni(5) bond length is 2.41 Å. Both Ni(1)-Ni(4) bond lengths are 2.45 Å. Both Ni(1)-Ni(6) bond lengths are 2.43 Å. There is one shorter (2.82 Å) and two longer (2.87 Å) Ni(1)-Ni(2) bond lengths. In the second Ni site, Ni(2) is bonded in a 9-coordinate geometry to three equivalent Ca(1), one Ni(3), one Ni(5), two equivalent Ni(4), two equivalent Ni(6), and three equivalent Ni(1) atoms. The Ni(2)-Ni(3) bond length is 2.44 Å. The Ni(2)-Ni(5) bond length is 2.42 Å. Both Ni(2)-Ni(4) bond lengths are 2.43 Å. Both Ni(2)-Ni(6) bond lengths are 2.43 Å. In the third Ni site, Ni(3) is bonded to four equivalent Ca(1), two equivalent Ni(1), two equivalent Ni(2), and four equivalent Ni(4) atoms to form distorted NiCa4Ni8 cuboctahedra that share corners with four equivalent Ni(3)Ca4Ni8 cuboctahedra, corners with four equivalent Ni(5)Ca4Ni8 cuboctahedra, corners with eight equivalent Ni(6)Ca4Ni8 cuboctahedra, edges with two equivalent Ni(3)Ca4Ni8 cuboctahedra, edges with eight equivalent Ni(6)Ca4Ni8 cuboctahedra,  an edgeedge with one H(1)Ca2Ni2 tetrahedra, faces with two equivalent Ni(5)Ca4Ni8 cuboctahedra, and faces with two equivalent H(1)Ca2Ni2 tetrahedra. There are two shorter (2.46 Å) and two longer (2.47 Å) Ni(3)-Ni(4) bond lengths. In the fourth Ni site, Ni(4) is bonded in a single-bond geometry to two equivalent Ni(1), two equivalent Ni(2), two equivalent Ni(3), and one H(1) atom. The Ni(4)-H(1) bond length is 1.57 Å. In the fifth Ni site, Ni(5) is bonded to four equivalent Ca(1), two equivalent Ni(1), two equivalent Ni(2), and four equivalent Ni(6) atoms to form NiCa4Ni8 cuboctahedra that share corners with four equivalent Ni(3)Ca4Ni8 cuboctahedra, corners with four equivalent Ni(5)Ca4Ni8 cuboctahedra, corners with four equivalent H(1)Ca2Ni2 tetrahedra, edges with two equivalent Ni(5)Ca4Ni8 cuboctahedra, faces with two equivalent Ni(3)Ca4Ni8 cuboctahedra, and faces with eight equivalent Ni(6)Ca4Ni8 cuboctahedra. All Ni(5)-Ni(6) bond lengths are 2.47 Å. In the sixth Ni site, Ni(6) is bonded to four equivalent Ca(1), two equivalent Ni(1), two equivalent Ni(2), two equivalent Ni(5), and two equivalent Ni(6) atoms to form NiCa4Ni8 cuboctahedra that share corners with four equivalent Ni(3)Ca4Ni8 cuboctahedra, corners with four equivalent Ni(6)Ca4Ni8 cuboctahedra, corners with four equivalent H(1)Ca2Ni2 tetrahedra, edges with two equivalent Ni(6)Ca4Ni8 cuboctahedra, edges with four equivalent Ni(3)Ca4Ni8 cuboctahedra, faces with four equivalent Ni(5)Ca4Ni8 cuboctahedra, and faces with four equivalent Ni(6)Ca4Ni8 cuboctahedra. There is one shorter (2.47 Å) and one longer (2.48 Å) Ni(6)-Ni(6) bond length. H(1) is bonded to two equivalent Ca(1) and two equivalent Ni(4) atoms to form HCa2Ni2 tetrahedra that share corners with four equivalent Ni(5)Ca4Ni8 cuboctahedra, corners with eight equivalent Ni(6)Ca4Ni8 cuboctahedra,  an edgeedge with one Ni(3)Ca4Ni8 cuboctahedra, and faces with two equivalent Ni(3)Ca4Ni8 cuboctahedra.