DOE OSTI2020
Er11Ge10 is delta Molybdenum Boride-like structured and crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. there are four inequivalent Er sites. In the first Er site, Er is bonded to seven Ge atoms to form a mixture of distorted edge, face, and corner-sharing ErGe7 pentagonal bipyramids. There are a spread of Er–Ge bond distances ranging from 2.87–3.31 Å. In the second Er site, Er is bonded in a 7-coordinate geometry to seven Ge atoms. There are a spread of Er–Ge bond distances ranging from 2.77–3.42 Å. In the third Er site, Er is bonded in a 8-coordinate geometry to eight Ge atoms. There are four shorter (3.20 Å) and four longer (3.24 Å) Er–Ge bond lengths. In the fourth Er site, Er is bonded in a 7-coordinate geometry to seven Ge atoms. There are a spread of Er–Ge bond distances ranging from 2.89–3.07 Å. There are five inequivalent Ge sites. In the first Ge site, Ge is bonded in a 2-coordinate geometry to eight Er atoms. In the second Ge site, Ge is bonded in a 9-coordinate geometry to eight Er atoms. In the third Ge site, Ge is bonded in a 9-coordinate geometry to seven Er and two equivalent Ge atoms. Both Ge–Ge bond lengths are 2.61 Å. In the fourth Ge site, Ge is bonded in a 8-coordinate geometry to eight Er atoms. In the fifth Ge site, Ge is bonded in a 9-coordinate geometry to eight Er and one Ge atom. The Ge–Ge bond length is 2.57 Å.