DOE OSTI2020
Nd3Ce(Fe14B)2 crystallizes in the orthorhombic Cmmm space group. The structure is three-dimensional. there are three inequivalent Nd sites. In the first Nd site, Nd is bonded in a 12-coordinate geometry to sixteen Fe atoms. There are a spread of Nd–Fe bond distances ranging from 3.04–3.25 Å. In the second Nd site, Nd is bonded in a 1-coordinate geometry to one Nd, two equivalent Ce, sixteen Fe, and one B atom. The Nd–Nd bond length is 3.51 Å. Both Nd–Ce bond lengths are 3.76 Å. There are a spread of Nd–Fe bond distances ranging from 3.06–3.37 Å. The Nd–B bond length is 2.87 Å. In the third Nd site, Nd is bonded in a 1-coordinate geometry to sixteen Fe and one B atom. There are a spread of Nd–Fe bond distances ranging from 3.06–3.37 Å. The Nd–B bond length is 2.88 Å. Ce is bonded in a 12-coordinate geometry to two equivalent Nd and sixteen Fe atoms. There are a spread of Ce–Fe bond distances ranging from 3.03–3.25 Å. There are twelve inequivalent Fe sites. In the first Fe site, Fe is bonded to one Nd, one Ce, and ten Fe atoms to form a mixture of distorted face, edge, and corner-sharing FeCeNdFe10 cuboctahedra. There are a spread of Fe–Fe bond distances ranging from 2.38–2.65 Å. In the second Fe site, Fe is bonded to two Nd and ten Fe atoms to form distorted FeNd2Fe10 cuboctahedra that share corners with ten FeNd2Fe10 cuboctahedra, edges with two FeNd2Fe10 cuboctahedra, and faces with eleven FeCeNdFe10 cuboctahedra. There are a spread of Fe–Fe bond distances ranging from 2.38–2.65 Å. In the third Fe site, Fe is bonded to two equivalent Nd, two equivalent Ce, and eight Fe atoms to form a mixture of face and corner-sharing FeCe2Nd2Fe8 cuboctahedra. All Fe–Fe bond lengths are 2.56 Å. In the fourth Fe site, Fe is bonded to four Nd and eight Fe atoms to form FeNd4Fe8 cuboctahedra that share corners with twenty FeNd2Fe10 cuboctahedra and faces with twelve FeCeNdFe10 cuboctahedra. All Fe–Fe bond lengths are 2.56 Å. In the fifth Fe site, Fe is bonded in a 2-coordinate geometry to one Nd, one Ce, and twelve Fe atoms. There are a spread of Fe–Fe bond distances ranging from 2.63–2.77 Å. In the sixth Fe site, Fe is bonded in a distorted water-like geometry to two equivalent Nd, four Fe, and two equivalent B atoms. There are two shorter (2.51 Å) and two longer (2.77 Å) Fe–Fe bond lengths. Both Fe–B bond lengths are 2.08 Å. In the seventh Fe site, Fe is bonded in a 2-coordinate geometry to two Nd and twelve Fe atoms. There are a spread of Fe–Fe bond distances ranging from 2.64–2.76 Å. In the eighth Fe site, Fe is bonded in a distorted water-like geometry to two equivalent Ce, four Fe, and two equivalent B atoms. Both Fe–Fe bond lengths are 2.50 Å. Both Fe–B bond lengths are 2.08 Å. In the ninth Fe site, Fe is bonded in a distorted single-bond geometry to one Nd, one Ce, seven Fe, and one B atom. The Fe–Fe bond length is 2.57 Å. The Fe–B bond length is 2.08 Å. In the tenth Fe site, Fe is bonded in a distorted single-bond geometry to two Nd, seven Fe, and one B atom. The Fe–Fe bond length is 2.57 Å. The Fe–B bond length is 2.09 Å. In the eleventh Fe site, Fe is bonded to two equivalent Nd, one Ce, and nine Fe atoms to form a mixture of distorted face, edge, and corner-sharing FeCeNd2Fe9 cuboctahedra. The Fe–Fe bond length is 2.43 Å. In the twelfth Fe site, Fe is bonded to three Nd and nine Fe atoms to form distorted FeNd3Fe9 cuboctahedra that share corners with fourteen FeCeNdFe10 cuboctahedra, edges with three FeNd2Fe10 cuboctahedra, and faces with twelve FeCeNdFe10 cuboctahedra. The Fe–Fe bond length is 2.42 Å. There are two inequivalent B sites. In the first B site, B is bonded in a 6-coordinate geometry to one Nd and six Fe atoms. In the second B site, B is bonded in a 6-coordinate geometry to one Nd and six Fe atoms.