Materials Data on Er3Co29(Si2B5)2 by Materials Project
CoEr3Co28(B5Si2)2 crystallizes in the tetragonal P4/nmm space group. The structure is three-dimensional and consists of two cobalt molecules and one Er3Co28(B5Si2)2 framework. In the Er3Co28(B5Si2)2 framework, there are two inequivalent Er3+ sites. In the first Er3+ site, Er3+ is bonded in a 8-coordinate geometry to four equivalent Si4- atoms. All Er–Si bond lengths are 3.26 Å. In the second Er3+ site, Er3+ is bonded in a 4-coordinate geometry to four equivalent Si4- atoms. All Er–Si bond lengths are 3.18 Å. There are six inequivalent Co+1.28+ sites. In the first Co+1.28+ site, Co+1.28+ is bonded in a distorted bent 150 degrees geometry to two B3- and two equivalent Si4- atoms. There are one shorter (2.12 Å) and one longer (2.15 Å) Co–B bond lengths. Both Co–Si bond lengths are 2.65 Å. In the second Co+1.28+ site, Co+1.28+ is bonded in a distorted single-bond geometry to one B3- and three equivalent Si4- atoms. The Co–B bond length is 1.90 Å. There are one shorter (2.37 Å) and two longer (2.42 Å) Co–Si bond lengths. In the third Co+1.28+ site, Co+1.28+ is bonded in a square co-planar geometry to four B3- atoms. There are three shorter (2.06 Å) and one longer (2.11 Å) Co–B bond lengths. In the fourth Co+1.28+ site, Co+1.28+ is bonded in a distorted T-shaped geometry to three B3- and one Si4- atom. There are one shorter (2.08 Å) and two longer (2.13 Å) Co–B bond lengths. The Co–Si bond length is 2.53 Å. In the fifth Co+1.28+ site, Co+1.28+ is bonded in a distorted rectangular see-saw-like geometry to three B3- and one Si4- atom. There are a spread of Co–B bond distances ranging from 2.03–2.13 Å. The Co–Si bond length is 2.33 Å. In the sixth Co+1.28+ site, Co+1.28+ is bonded in a distorted rectangular see-saw-like geometry to three B3- and one Si4- atom. There are a spread of Co–B bond distances ranging from 2.05–2.11 Å. The Co–Si bond length is 2.34 Å. There are four inequivalent B3- sites. In the first B3- site, B3- is bonded in a 9-coordinate geometry to eight Co+1.28+ and one B3- atom. The B–B bond length is 1.96 Å. In the second B3- site, B3- is bonded in a 9-coordinate geometry to eight Co+1.28+ and one B3- atom. In the third B3- site, B3- is bonded in a 7-coordinate geometry to seven Co+1.28+ atoms. In the fourth B3- site, B3- is bonded in a 9-coordinate geometry to eight Co+1.28+ and one B3- atom. The B–B bond length is 2.04 Å. Si4- is bonded in a 12-coordinate geometry to three Er3+ and nine Co+1.28+ atoms.