Materials Data on Er2Fe14Si3 by Materials Project

Er2Fe14Si3 crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. there are two inequivalent Er sites. In the first Er site, Er is bonded in a 6-coordinate geometry to eighteen Fe atoms. There are a spread of Er–Fe bond distances ranging from 2.86–3.24 Å. In the second Er site, Er is bonded in a 8-coordinate geometry to fourteen Fe and six equivalent Si atoms. There are a spread of Er–Fe bond distances ranging from 2.90–3.07 Å. All Er–Si bond lengths are 3.15 Å. There are three inequivalent Fe sites. In the first Fe site, Fe is bonded in a 5-coordinate geometry to one Er, ten Fe, and three equivalent Si atoms. There are a spread of Fe–Fe bond distances ranging from 2.29–2.80 Å. All Fe–Si bond lengths are 2.56 Å. In the second Fe site, Fe is bonded in a 12-coordinate geometry to two Er, eight Fe, and two equivalent Si atoms. There are a spread of Fe–Fe bond distances ranging from 2.50–2.59 Å. Both Fe–Si bond lengths are 2.43 Å. In the third Fe site, Fe is bonded to three Er, seven Fe, and two equivalent Si atoms to form distorted FeEr3Fe7Si2 cuboctahedra that share corners with five equivalent SiEr2Fe10 cuboctahedra, corners with ten equivalent FeEr3Fe7Si2 cuboctahedra, edges with three equivalent SiEr2Fe10 cuboctahedra, edges with five equivalent FeEr3Fe7Si2 cuboctahedra, faces with two equivalent SiEr2Fe10 cuboctahedra, and faces with eight equivalent FeEr3Fe7Si2 cuboctahedra. Both Fe–Fe bond lengths are 2.43 Å. Both Fe–Si bond lengths are 2.39 Å. Si is bonded to two equivalent Er and ten Fe atoms to form distorted SiEr2Fe10 cuboctahedra that share corners with four equivalent SiEr2Fe10 cuboctahedra, corners with ten equivalent FeEr3Fe7Si2 cuboctahedra, edges with six equivalent FeEr3Fe7Si2 cuboctahedra, faces with four equivalent FeEr3Fe7Si2 cuboctahedra, and faces with six equivalent SiEr2Fe10 cuboctahedra.

Er2Fe14Si3属于六方晶系P6_3/mmc空间群，其结构为三维网络结构。体系中存在两种不等价的铒（Er）位点：在第一个铒位点中，铒原子以六配位几何构型与18个铁（Fe）原子成键，Er-Fe键的键长分布范围为2.86~3.24 Å；在第二个铒位点中，铒原子以八配位几何构型与14个铁原子及6个等价的硅（Si）原子成键，Er-Fe键距分布范围为2.90~3.07 Å，所有Er-Si键长均为3.15 Å。
体系中存在三种不等价的铁位点：第一个铁位点中，铁原子以五配位几何构型与1个铒原子、10个铁原子及3个等价的硅原子成键，Fe-Fe键距分布范围为2.29~2.80 Å，所有Fe-Si键长均为2.56 Å；第二个铁位点中，铁原子以十二配位几何构型与2个铒原子、8个铁原子及2个等价的硅原子成键，Fe-Fe键距分布范围为2.50~2.59 Å，两条Fe-Si键长均为2.43 Å；第三个铁位点中，铁原子与3个铒原子、7个铁原子及2个等价的硅原子成键，形成畸变的FeEr3Fe7Si2型立方八面体结构单元，该结构单元分别与5个等价的SiEr2Fe10型立方八面体共顶点、与10个等价的FeEr3Fe7Si2型立方八面体共顶点，与3个等价的SiEr2Fe10型立方八面体共棱、与5个等价的FeEr3Fe7Si2型立方八面体共棱，与2个等价的SiEr2Fe10型立方八面体共面、与8个等价的FeEr3Fe7Si2型立方八面体共面，该位点的Fe-Fe键长均为2.43 Å，Fe-Si键长均为2.39 Å。
硅原子与2个等价的铒原子及10个铁原子成键，形成畸变的SiEr2Fe10型立方八面体结构单元，该结构单元分别与4个等价的SiEr2Fe10型立方八面体共顶点、与10个等价的FeEr3Fe7Si2型立方八面体共顶点，与6个等价的FeEr3Fe7Si2型立方八面体共棱，与4个等价的FeEr3Fe7Si2型立方八面体共面、与6个等价的SiEr2Fe10型立方八面体共面。