DOE OSTI2020
Dy2Co17 crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. there are two inequivalent Dy sites. In the first Dy site, Dy is bonded in a 2-coordinate geometry to twenty Co atoms. There are a spread of Dy–Co bond distances ranging from 2.90–3.14 Å. In the second Dy site, Dy is bonded in a 12-coordinate geometry to eighteen Co atoms. There are a spread of Dy–Co bond distances ranging from 2.95–3.25 Å. There are four inequivalent Co sites. In the first Co site, Co is bonded to two Dy and ten Co atoms to form a mixture of distorted edge, corner, and face-sharing CoDy2Co10 cuboctahedra. There are a spread of Co–Co bond distances ranging from 2.34–2.66 Å. In the second Co site, Co is bonded to two equivalent Dy and ten Co atoms to form CoDy2Co10 cuboctahedra that share corners with twenty-two CoDy3Co9 cuboctahedra, edges with ten CoDy3Co9 cuboctahedra, and faces with eighteen CoDy2Co10 cuboctahedra. There are four shorter (2.40 Å) and two longer (2.55 Å) Co–Co bond lengths. In the third Co site, Co is bonded in a 2-coordinate geometry to one Dy and thirteen Co atoms. There are one shorter (2.31 Å) and three longer (2.61 Å) Co–Co bond lengths. In the fourth Co site, Co is bonded to three Dy and nine Co atoms to form distorted CoDy3Co9 cuboctahedra that share corners with twenty-three CoDy3Co9 cuboctahedra, edges with ten CoDy3Co9 cuboctahedra, and faces with twenty CoDy2Co10 cuboctahedra. Both Co–Co bond lengths are 2.42 Å.