Materials Data on Eu3(MgGe)5 by Materials Project

Abstract

Eu3(MgGe)5 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are five inequivalent Mg sites. In the first Mg site, Mg is bonded to four Ge atoms to form MgGe4 tetrahedra that share corners with five MgGe4 tetrahedra and edges with four MgEuGe4 tetrahedra. There are two shorter (2.74 Å) and two longer (2.77 Å) Mg–Ge bond lengths. In the second Mg site, Mg is bonded to one Eu and four Ge atoms to form distorted MgEuGe4 tetrahedra that share corners with seven MgGe4 tetrahedra, edges with four MgEu2Ge4 tetrahedra, and faces with two equivalent MgEu2Ge4 tetrahedra. The Mg–Eu bond length is 3.33 Å. There are a spread of Mg–Ge bond distances ranging from 2.71–2.83 Å. In the third Mg site, Mg is bonded to one Eu and four Ge atoms to form MgEuGe4 tetrahedra that share corners with nine MgEuGe4 tetrahedra, edges with two equivalent MgEuGe4 tetrahedra, and faces with two equivalent MgEu2Ge4 tetrahedra. The Mg–Eu bond length is 3.34 Å. There are one shorter (2.69 Å) and three longer (2.78 Å) Mg–Ge bond lengths. In the fourth Mg site, Mg is bonded to two equivalent Eu and four Ge atoms to form distorted MgEu2Ge4 tetrahedra that share corners with eight MgGe4 tetrahedra, edges with five MgEuGe4 tetrahedra, and faces with three MgEuGe4 tetrahedra. Both Mg–Eu bond lengths are 3.38 Å. There are a spread of Mg–Ge bond distances ranging from 2.77–2.81 Å. In the fifth Mg site, Mg is bonded to two equivalent Eu and four Ge atoms to form distorted MgEu2Ge4 tetrahedra that share corners with nine MgGe4 tetrahedra, edges with three MgEu2Ge4 tetrahedra, and faces with three MgEuGe4 tetrahedra. Both Mg–Eu bond lengths are 3.32 Å. There are a spread of Mg–Ge bond distances ranging from 2.74–2.82 Å. There are three inequivalent Eu sites. In the first Eu site, Eu is bonded in a 7-coordinate geometry to seven Ge atoms. There are a spread of Eu–Ge bond distances ranging from 3.26–3.46 Å. In the second Eu site, Eu is bonded in a 6-coordinate geometry to six Ge atoms. There are a spread of Eu–Ge bond distances ranging from 3.28–3.42 Å. In the third Eu site, Eu is bonded in a 6-coordinate geometry to six Mg and six Ge atoms. There are a spread of Eu–Ge bond distances ranging from 3.15–3.24 Å. There are five inequivalent Ge sites. In the first Ge site, Ge is bonded in a 9-coordinate geometry to four Mg, four Eu, and one Ge atom. The Ge–Ge bond length is 2.53 Å. In the second Ge site, Ge is bonded in a 7-coordinate geometry to six Mg and one Eu atom. In the third Ge site, Ge is bonded in a 1-coordinate geometry to one Mg, six Eu, and two Ge atoms. The Ge–Ge bond length is 2.60 Å. In the fourth Ge site, Ge is bonded in a 9-coordinate geometry to five Mg and four Eu atoms. In the fifth Ge site, Ge is bonded in a 9-coordinate geometry to four Mg, four Eu, and one Ge atom.