DOE OSTI2020
W11Ni2C4 crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. there are ten inequivalent W sites. In the first W site, W is bonded in a 1-coordinate geometry to eleven W, one Ni, and one C atom. There are a spread of W–W bond distances ranging from 2.66–3.00 Å. The W–Ni bond length is 2.61 Å. The W–C bond length is 2.69 Å. In the second W site, W is bonded to twelve W atoms to form WW12 cuboctahedra that share corners with four equivalent CNi2W4 octahedra, faces with two equivalent WW12 cuboctahedra, and faces with four equivalent CNiW5 octahedra. The corner-sharing octahedral tilt angles are 46°. There are a spread of W–W bond distances ranging from 2.61–2.99 Å. In the third W site, W is bonded in a 2-coordinate geometry to two equivalent W and two Ni atoms. Both W–W bond lengths are 2.61 Å. There are one shorter (2.59 Å) and one longer (2.64 Å) W–Ni bond lengths. In the fourth W site, W is bonded in a 2-coordinate geometry to two equivalent W and two equivalent Ni atoms. Both W–W bond lengths are 2.57 Å. Both W–Ni bond lengths are 2.61 Å. In the fifth W site, W is bonded to twelve W atoms to form distorted WW12 cuboctahedra that share edges with six CNi2W4 octahedra and faces with three WW12 cuboctahedra. There are a spread of W–W bond distances ranging from 2.90–3.01 Å. In the sixth W site, W is bonded in a distorted bent 150 degrees geometry to two W and two C atoms. There are one shorter (2.12 Å) and one longer (2.14 Å) W–C bond lengths. In the seventh W site, W is bonded in a 2-coordinate geometry to two W and two equivalent C atoms. Both W–C bond lengths are 2.12 Å. In the eighth W site, W is bonded in a 2-coordinate geometry to three W and two C atoms. There are one shorter (2.13 Å) and one longer (2.15 Å) W–C bond lengths. In the ninth W site, W is bonded in a distorted bent 150 degrees geometry to three W and two equivalent C atoms. Both W–C bond lengths are 2.14 Å. In the tenth W site, W is bonded in a 3-coordinate geometry to two W and three C atoms. There are one shorter (2.02 Å) and two longer (2.18 Å) W–C bond lengths. There are three inequivalent Ni sites. In the first Ni site, Ni is bonded in a distorted T-shaped geometry to two equivalent W and three C atoms. There is one shorter (1.86 Å) and two longer (2.09 Å) Ni–C bond length. In the second Ni site, Ni is bonded in a 3-coordinate geometry to two W and three C atoms. There is one shorter (1.94 Å) and two longer (2.04 Å) Ni–C bond length. In the third Ni site, Ni is bonded in a 3-coordinate geometry to two equivalent W and three C atoms. There is one shorter (1.90 Å) and two longer (2.05 Å) Ni–C bond length. There are four inequivalent C sites. In the first C site, C is bonded in a 1-coordinate geometry to four W and one Ni atom. In the second C site, C is bonded in a trigonal planar geometry to three Ni atoms. In the third C site, C is bonded to five W and one Ni atom to form CNiW5 octahedra that share corners with six CNiW5 octahedra, edges with two equivalent WW12 cuboctahedra, and a faceface with one WW12 cuboctahedra. The corner-sharing octahedra tilt angles range from 22–45°. In the fourth C site, C is bonded to four W and two Ni atoms to form CNi2W4 octahedra that share corners with two equivalent WW12 cuboctahedra, corners with six CNiW5 octahedra, and edges with two equivalent WW12 cuboctahedra. The corner-sharing octahedra tilt angles range from 3–41°.