DOE OSTI2020
Nd3Co8Sn4 is Hexagonal Laves-derived structured and crystallizes in the hexagonal P6_3mc space group. The structure is three-dimensional. Nd is bonded in a 12-coordinate geometry to eight Co and six Sn atoms. There are a spread of Nd–Co bond distances ranging from 3.17–3.58 Å. There are a spread of Nd–Sn bond distances ranging from 3.23–3.33 Å. There are four inequivalent Co sites. In the first Co site, Co is bonded to two equivalent Nd, seven Co, and three equivalent Sn atoms to form distorted CoNd2Co7Sn3 cuboctahedra that share corners with nine CoNd4Co4Sn4 cuboctahedra and faces with fourteen CoNd2Co7Sn3 cuboctahedra. There are a spread of Co–Co bond distances ranging from 2.37–2.57 Å. All Co–Sn bond lengths are 2.68 Å. In the second Co site, Co is bonded to four equivalent Nd, four Co, and four Sn atoms to form a mixture of distorted face and corner-sharing CoNd4Co4Sn4 cuboctahedra. The Co–Co bond length is 2.47 Å. There are a spread of Co–Sn bond distances ranging from 2.72–2.84 Å. In the third Co site, Co is bonded to nine Co and three equivalent Sn atoms to form CoCo9Sn3 cuboctahedra that share corners with three equivalent CoNd4Co4Sn4 cuboctahedra and faces with fourteen CoNd2Co7Sn3 cuboctahedra. All Co–Sn bond lengths are 2.71 Å. In the fourth Co site, Co is bonded in a 10-coordinate geometry to six equivalent Nd and four Sn atoms. There are three shorter (2.56 Å) and one longer (2.76 Å) Co–Sn bond lengths. There are two inequivalent Sn sites. In the first Sn site, Sn is bonded in a 10-coordinate geometry to six equivalent Nd and four Co atoms. In the second Sn site, Sn is bonded in a 12-coordinate geometry to four equivalent Nd and eight Co atoms.