Materials Data on Pr4Mg5Ge6 by Materials Project

Abstract

Mg5Pr4Ge6 crystallizes in the orthorhombic Cmc2_1 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 distorted MgGe4 tetrahedra that share corners with six PrGe6 octahedra, corners with four MgGe4 tetrahedra, and edges with five MgGe4 tetrahedra. The corner-sharing octahedra tilt angles range from 55–60°. There are a spread of Mg–Ge bond distances ranging from 2.73–2.79 Å. In the second Mg site, Mg is bonded to four Ge atoms to form distorted MgGe4 tetrahedra that share corners with two PrGe6 octahedra, corners with eight MgGe4 tetrahedra, edges with four PrGe6 octahedra, and edges with two MgGe4 tetrahedra. The corner-sharing octahedra tilt angles range from 9–11°. There are a spread of Mg–Ge bond distances ranging from 2.74–2.80 Å. In the third Mg site, Mg is bonded to four Ge atoms to form distorted MgGe4 tetrahedra that share corners with two equivalent PrGe6 octahedra, corners with six MgGe4 tetrahedra, edges with three PrGe6 octahedra, and edges with two equivalent MgGe4 tetrahedra. The corner-sharing octahedral tilt angles are 15°. There are a spread of Mg–Ge bond distances ranging from 2.67–2.87 Å. In the fourth Mg site, Mg is bonded to four Ge atoms to form distorted MgGe4 tetrahedra that share corners with two equivalent PrGe6 octahedra, corners with nine MgGe4 tetrahedra, edges with two equivalent PrGe6 octahedra, and an edgeedge with one MgGe4 tetrahedra. The corner-sharing octahedral tilt angles are 63°. There are a spread of Mg–Ge bond distances ranging from 2.63–2.92 Å. In the fifth Mg site, Mg is bonded to four Ge atoms to form MgGe4 tetrahedra that share corners with two equivalent PrGe6 octahedra, corners with seven MgGe4 tetrahedra, edges with three PrGe6 octahedra, and edges with two equivalent MgGe4 tetrahedra. The corner-sharing octahedral tilt angles are 13°. There are a spread of Mg–Ge bond distances ranging from 2.71–2.85 Å. There are four inequivalent Pr sites. In the first Pr site, Pr is bonded in a 7-coordinate geometry to seven Ge atoms. There are a spread of Pr–Ge bond distances ranging from 3.18–3.40 Å. In the second Pr site, Pr is bonded in a 6-coordinate geometry to six Ge atoms. There are a spread of Pr–Ge bond distances ranging from 3.19–3.24 Å. In the third Pr site, Pr is bonded to six Ge atoms to form PrGe6 octahedra that share a cornercorner with one PrGe6 octahedra, corners with six MgGe4 tetrahedra, edges with four PrGe6 octahedra, and edges with seven MgGe4 tetrahedra. The corner-sharing octahedral tilt angles are 43°. There are a spread of Pr–Ge bond distances ranging from 3.09–3.24 Å. In the fourth Pr site, Pr is bonded to six Ge atoms to form PrGe6 octahedra that share a cornercorner with one PrGe6 octahedra, corners with eight MgGe4 tetrahedra, edges with four PrGe6 octahedra, and edges with five MgGe4 tetrahedra. The corner-sharing octahedral tilt angles are 43°. There are a spread of Pr–Ge bond distances ranging from 3.06–3.19 Å. There are six inequivalent Ge sites. In the first Ge site, Ge is bonded in a 7-coordinate geometry to four Mg and three Pr atoms. In the second Ge site, Ge is bonded to four Mg and three Pr atoms to form distorted edge-sharing GePr3Mg4 pentagonal bipyramids. In the third Ge site, Ge is bonded to four Mg and three Pr atoms to form distorted edge-sharing GePr3Mg4 pentagonal bipyramids. In the fourth Ge site, Ge is bonded in a 8-coordinate geometry to one Mg, six Pr, and one Ge atom. The Ge–Ge bond length is 2.60 Å. In the fifth Ge site, Ge is bonded in a 9-coordinate geometry to two Mg, six Pr, and one Ge atom. In the sixth Ge site, Ge is bonded in a 9-coordinate geometry to five Mg and four Pr atoms.