Materials Data on Nb4Fe3Si5 by Materials Project

Abstract

Nb4Fe3Si5 crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. there are two inequivalent Nb+2.75+ sites. In the first Nb+2.75+ site, Nb+2.75+ is bonded in a 7-coordinate geometry to seven Si4- atoms. There are a spread of Nb–Si bond distances ranging from 2.77–2.85 Å. In the second Nb+2.75+ site, Nb+2.75+ is bonded in a 8-coordinate geometry to eight Si4- atoms. There are a spread of Nb–Si bond distances ranging from 2.81–2.83 Å. There are two inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded in a 5-coordinate geometry to five Si4- atoms. There are a spread of Fe–Si bond distances ranging from 2.35–2.42 Å. In the second Fe3+ site, Fe3+ is bonded in a 4-coordinate geometry to four equivalent Si4- atoms. There are two shorter (2.41 Å) and two longer (2.49 Å) Fe–Si bond lengths. There are three inequivalent Si4- sites. In the first Si4- site, Si4- is bonded to six Nb+2.75+, four Fe3+, and two equivalent Si4- atoms to form SiNb6Fe4Si2 cuboctahedra that share corners with fourteen SiNb6Fe4Si2 cuboctahedra, edges with six SiNb6Fe2Si4 cuboctahedra, and faces with eight SiNb6Fe2Si4 cuboctahedra. There are one shorter (2.46 Å) and one longer (2.49 Å) Si–Si bond lengths. In the second Si4- site, Si4- is bonded to six Nb+2.75+, two equivalent Fe3+, and four equivalent Si4- atoms to form a mixture of edge, face, and corner-sharing SiNb6Fe2Si4 cuboctahedra. There are two shorter (2.42 Å) and two longer (2.48 Å) Si–Si bond lengths. In the third Si4- site, Si4- is bonded to six Nb+2.75+, two equivalent Fe3+, and four Si4- atoms to form SiNb6Fe2Si4 cuboctahedra that share corners with ten SiNb6Fe2Si4 cuboctahedra, edges with six SiNb6Fe4Si2 cuboctahedra, and faces with ten SiNb6Fe2Si4 cuboctahedra. There are one shorter (2.46 Å) and one longer (2.49 Å) Si–Si bond lengths.