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YbFe2 is Cubic Laves structured and crystallizes in the cubic Fd-3m space group. The structure is three-dimensional. Yb is bonded in a 12-coordinate geometry to twelve equivalent Fe atoms. All Yb–Fe bond lengths are 2.96 Å. Fe is bonded to six equivalent Yb and six equivalent Fe atoms to form a mixture of edge, face, and corner-sharing FeYb6Fe6 cuboctahedra. All Fe–Fe bond lengths are 2.52 Å.
Yb6Fe23 crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. Yb is bonded in a 12-coordinate geometry to twelve Fe atoms. There are a spread of Yb–Fe bond distances ranging from 2.86–3.02 Å. There are four inequivalent Fe sites. In the first Fe site, Fe is bonded in a body-centered cubic geometry to eight equivalent Fe atoms. All Fe–Fe bond lengths are 2.48 Å. In the second Fe site, Fe is bonded in a distorted q6 geometry to three equivalent Yb and nine Fe atoms. There are a spread of Fe–Fe bond distances ranging from 2.44–2.61 Å. In the third Fe site, Fe is bonded to four equivalent Yb and eight Fe atoms to form a mixture of corner and face-sharing FeYb4Fe8 cuboctahedra. All Fe–Fe bond lengths are 2.62 Å. In the fourth Fe site, Fe is bonded in a 3-coordinate geometry to three equivalent Yb and ten Fe atoms. All Fe–Fe bond lengths are 2.87 Å.
Yb2Fe17 crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. there are two inequivalent Yb sites. In the first Yb site, Yb is bonded in a 12-coordinate geometry to eighteen Fe atoms. There are a spread of Yb–Fe bond distances ranging from 3.00–3.30 Å. In the second Yb site, Yb is bonded in a 2-coordinate geometry to twenty Fe atoms. There are a spread of Yb–Fe bond distances ranging from 2.91–3.20 Å. There are four inequivalent Fe sites. In the first Fe site, Fe is bonded in a 2-coordinate geometry to one Yb and thirteen Fe atoms. There are a spread of Fe–Fe bond distances ranging from 2.42–2.75 Å. In the second Fe site, Fe is bonded to two equivalent Yb and ten Fe atoms to form FeYb2Fe10 cuboctahedra that share corners with fourteen FeYb2Fe10 cuboctahedra, edges with six equivalent FeYb3Fe9 cuboctahedra, and faces with ten FeYb2Fe10 cuboctahedra. There are four shorter (2.44 Å) and four longer (2.46 Å) Fe–Fe bond lengths. In the third Fe site, Fe is bonded in a 12-coordinate geometry to two Yb and ten Fe atoms. There are a spread of Fe–Fe bond distances ranging from 2.41–2.60 Å. In the fourth Fe site, Fe is bonded to three Yb and nine Fe atoms to form a mixture of distorted edge, corner, and face-sharing FeYb3Fe9 cuboctahedra. Both Fe–Fe bond lengths are 2.46 Å.