DOE OSTI2020
Nb(Ni4Ga)3 is beta Cu3Ti-derived structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. Nb is bonded to twelve Ni atoms to form NbNi12 cuboctahedra that share corners with four equivalent NbNi12 cuboctahedra, corners with eight equivalent GaNi12 cuboctahedra, edges with twenty-four NiNb2Ga2Ni8 cuboctahedra, faces with two equivalent GaNi12 cuboctahedra, faces with four equivalent NbNi12 cuboctahedra, and faces with twelve NiNb4Ni8 cuboctahedra. There are four shorter (2.55 Å) and eight longer (2.57 Å) Nb–Ni bond lengths. There are seven inequivalent Ni sites. In the first Ni site, Ni is bonded to four equivalent Nb and eight Ni atoms to form NiNb4Ni8 cuboctahedra that share corners with twelve NiNb4Ni8 cuboctahedra, edges with eight equivalent GaNi12 cuboctahedra, edges with sixteen NiNb2Ga2Ni8 cuboctahedra, faces with four equivalent NbNi12 cuboctahedra, and faces with fourteen NiNb4Ni8 cuboctahedra. All Ni–Ni bond lengths are 2.57 Å. In the second Ni site, Ni is bonded to eight Ni and four equivalent Ga atoms to form NiGa4Ni8 cuboctahedra that share corners with twelve NiNb4Ni8 cuboctahedra, edges with four equivalent NbNi12 cuboctahedra, edges with four equivalent GaNi12 cuboctahedra, edges with sixteen NiNb2Ga2Ni8 cuboctahedra, faces with four equivalent GaNi12 cuboctahedra, and faces with fourteen NiNb4Ni8 cuboctahedra. All Ni–Ni bond lengths are 2.52 Å. All Ni–Ga bond lengths are 2.56 Å. In the third Ni site, Ni is bonded to eight equivalent Ni and four equivalent Ga atoms to form NiGa4Ni8 cuboctahedra that share corners with twelve NiGa4Ni8 cuboctahedra, edges with eight equivalent GaNi12 cuboctahedra, edges with sixteen equivalent NiGa4Ni8 cuboctahedra, faces with four equivalent GaNi12 cuboctahedra, and faces with fourteen NiGa4Ni8 cuboctahedra. All Ni–Ni bond lengths are 2.54 Å. All Ni–Ga bond lengths are 2.55 Å. In the fourth Ni site, Ni is bonded to two equivalent Nb, eight Ni, and two equivalent Ga atoms to form NiNb2Ga2Ni8 cuboctahedra that share corners with twelve NiNb2Ga2Ni8 cuboctahedra, edges with four equivalent NbNi12 cuboctahedra, edges with four equivalent GaNi12 cuboctahedra, edges with sixteen NiNb4Ni8 cuboctahedra, faces with two equivalent NbNi12 cuboctahedra, faces with two equivalent GaNi12 cuboctahedra, and faces with fourteen NiNb4Ni8 cuboctahedra. All Ni–Ni bond lengths are 2.55 Å. Both Ni–Ga bond lengths are 2.55 Å. In the fifth Ni site, Ni is bonded to eight Ni and four Ga atoms to form NiGa4Ni8 cuboctahedra that share corners with twelve NiNb2Ga2Ni8 cuboctahedra, edges with eight GaNi12 cuboctahedra, edges with sixteen NiGa4Ni8 cuboctahedra, faces with four GaNi12 cuboctahedra, and faces with fourteen NiGa4Ni8 cuboctahedra. All Ni–Ni bond lengths are 2.55 Å. There are two shorter (2.49 Å) and two longer (2.54 Å) Ni–Ga bond lengths. In the sixth Ni site, Ni is bonded to two equivalent Nb, eight Ni, and two equivalent Ga atoms to form NiNb2Ga2Ni8 cuboctahedra that share corners with twelve NiGa4Ni8 cuboctahedra, edges with four equivalent NbNi12 cuboctahedra, edges with four equivalent GaNi12 cuboctahedra, edges with sixteen NiNb4Ni8 cuboctahedra, faces with two equivalent NbNi12 cuboctahedra, faces with two equivalent GaNi12 cuboctahedra, and faces with fourteen NiNb4Ni8 cuboctahedra. Both Ni–Ga bond lengths are 2.55 Å. In the seventh Ni site, Ni is bonded to two equivalent Nb, eight Ni, and two equivalent Ga atoms to form NiNb2Ga2Ni8 cuboctahedra that share corners with twelve NiGa4Ni8 cuboctahedra, edges with four equivalent NbNi12 cuboctahedra, edges with four equivalent GaNi12 cuboctahedra, edges with sixteen NiNb4Ni8 cuboctahedra, faces with two equivalent NbNi12 cuboctahedra, faces with two equivalent GaNi12 cuboctahedra, and faces with fourteen NiNb4Ni8 cuboctahedra. There are two shorter (2.52 Å) and four longer (2.55 Å) Ni–Ni bond lengths. Both Ni–Ga bond lengths are 2.55 Å. There are two inequivalent Ga sites. In the first Ga site, Ga is bonded to twelve Ni atoms to form GaNi12 cuboctahedra that share corners with four equivalent NbNi12 cuboctahedra, corners with eight GaNi12 cuboctahedra, edges with twenty-four NiNb4Ni8 cuboctahedra, a faceface with one NbNi12 cuboctahedra, faces with five GaNi12 cuboctahedra, and faces with twelve NiGa4Ni8 cuboctahedra. In the second Ga site, Ga is bonded to twelve Ni atoms to form GaNi12 cuboctahedra that share corners with twelve GaNi12 cuboctahedra, edges with twenty-four NiGa4Ni8 cuboctahedra, faces with six GaNi12 cuboctahedra, and faces with twelve NiGa4Ni8 cuboctahedra.