Materials Data on CaFe4As3 by Materials Project
CaFe4As3 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Ca is bonded in a 7-coordinate geometry to seven As atoms. There are a spread of Ca–As bond distances ranging from 2.96–3.28 Å. There are four inequivalent Fe sites. In the first Fe site, Fe is bonded to four As atoms to form a mixture of distorted edge and corner-sharing FeAs4 tetrahedra. There are a spread of Fe–As bond distances ranging from 2.38–2.41 Å. In the second Fe site, Fe is bonded to four As atoms to form a mixture of distorted edge and corner-sharing FeAs4 tetrahedra. There are a spread of Fe–As bond distances ranging from 2.43–2.46 Å. In the third Fe site, Fe is bonded in a 5-coordinate geometry to five As atoms. There are a spread of Fe–As bond distances ranging from 2.40–2.61 Å. In the fourth Fe site, Fe is bonded to four As atoms to form a mixture of distorted edge and corner-sharing FeAs4 tetrahedra. There are a spread of Fe–As bond distances ranging from 2.34–2.38 Å. There are three inequivalent As sites. In the first As site, As is bonded in a 9-coordinate geometry to two equivalent Ca and seven Fe atoms. In the second As site, As is bonded in a 8-coordinate geometry to two equivalent Ca and six Fe atoms. In the third As site, As is bonded in a 7-coordinate geometry to three equivalent Ca and four Fe atoms.