Materials Data on EuGeS3 by Materials Project
EuGeS3 is Esseneite-derived structured and crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are three inequivalent Eu2+ sites. In the first Eu2+ site, Eu2+ is bonded in a 8-coordinate geometry to eight S2- atoms. There are a spread of Eu–S bond distances ranging from 3.00–3.25 Å. In the second Eu2+ site, Eu2+ is bonded to six S2- atoms to form EuS6 octahedra that share corners with six GeS4 tetrahedra and an edgeedge with one EuS6 octahedra. There are a spread of Eu–S bond distances ranging from 2.92–3.03 Å. In the third Eu2+ site, Eu2+ is bonded in a 7-coordinate geometry to seven S2- atoms. There are a spread of Eu–S bond distances ranging from 2.97–3.24 Å. There are three inequivalent Ge4+ sites. In the first Ge4+ site, Ge4+ is bonded to four S2- atoms to form GeS4 tetrahedra that share corners with two equivalent EuS6 octahedra and corners with two GeS4 tetrahedra. The corner-sharing octahedra tilt angles range from 64–71°. There are a spread of Ge–S bond distances ranging from 2.21–2.27 Å. In the second Ge4+ site, Ge4+ is bonded to four S2- atoms to form GeS4 tetrahedra that share a cornercorner with one EuS6 octahedra and corners with two GeS4 tetrahedra. The corner-sharing octahedral tilt angles are 66°. There are a spread of Ge–S bond distances ranging from 2.20–2.28 Å. In the third Ge4+ site, Ge4+ is bonded to four S2- atoms to form GeS4 tetrahedra that share corners with three equivalent EuS6 octahedra and corners with two GeS4 tetrahedra. The corner-sharing octahedra tilt angles range from 58–64°. There are a spread of Ge–S bond distances ranging from 2.21–2.30 Å. There are nine inequivalent S2- sites. In the first S2- site, S2- is bonded in a 4-coordinate geometry to three Eu2+ and one Ge4+ atom. In the second S2- site, S2- is bonded in a 2-coordinate geometry to one Eu2+ and two Ge4+ atoms. In the third S2- site, S2- is bonded in a 2-coordinate geometry to one Eu2+ and two Ge4+ atoms. In the fourth S2- site, S2- is bonded in a 4-coordinate geometry to three Eu2+ and one Ge4+ atom. In the fifth S2- site, S2- is bonded to three Eu2+ and one Ge4+ atom to form a mixture of distorted edge and corner-sharing SEu3Ge tetrahedra. In the sixth S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to three Eu2+ and one Ge4+ atom. In the seventh S2- site, S2- is bonded in a 3-coordinate geometry to one Eu2+ and two Ge4+ atoms. In the eighth S2- site, S2- is bonded in a 4-coordinate geometry to three Eu2+ and one Ge4+ atom. In the ninth S2- site, S2- is bonded to three Eu2+ and one Ge4+ atom to form a mixture of distorted edge and corner-sharing SEu3Ge tetrahedra.