Materials Data on EuSi2Ni9 by Materials Project
EuNi9Si2 crystallizes in the tetragonal I4_1/amd space group. The structure is three-dimensional. Eu is bonded in a 10-coordinate geometry to eighteen Ni atoms. There are a spread of Eu–Ni bond distances ranging from 3.04–3.17 Å. There are two inequivalent Ni sites. In the first Ni site, Ni is bonded in a 6-coordinate geometry to two equivalent Eu, eight equivalent Ni, and four equivalent Si atoms. All Ni–Ni bond lengths are 2.61 Å. All Ni–Si bond lengths are 2.57 Å. In the second Ni site, Ni is bonded to two equivalent Eu, eight Ni, and two equivalent Si atoms to form a mixture of distorted corner, edge, and face-sharing NiEu2Si2Ni8 cuboctahedra. There are a spread of Ni–Ni bond distances ranging from 2.42–2.59 Å. There are one shorter (2.33 Å) and one longer (2.38 Å) Ni–Si bond lengths. Si is bonded in a 12-coordinate geometry to ten Ni atoms.