Materials Data on Mn9(NbGe4)2 by Materials Project
Mn9(NbGe4)2 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are two inequivalent Nb sites. In the first Nb site, Nb is bonded to seven Ge atoms to form distorted NbGe7 pentagonal bipyramids that share a cornercorner with one MnGe7 pentagonal bipyramid, corners with three NbGe7 pentagonal bipyramids, an edgeedge with one MnGe7 pentagonal bipyramid, edges with two equivalent NbGe7 pentagonal bipyramids, and faces with two equivalent NbGe7 pentagonal bipyramids. There are a spread of Nb–Ge bond distances ranging from 2.62–2.79 Å. In the second Nb site, Nb is bonded to seven Ge atoms to form distorted NbGe7 pentagonal bipyramids that share corners with three NbGe7 pentagonal bipyramids, corners with four equivalent MnGe7 pentagonal bipyramids, and faces with two equivalent NbGe7 pentagonal bipyramids. There are a spread of Nb–Ge bond distances ranging from 2.69–2.82 Å. There are seven inequivalent Mn sites. In the first Mn site, Mn is bonded in a 5-coordinate geometry to five Ge atoms. There are a spread of Mn–Ge bond distances ranging from 2.48–2.51 Å. In the second Mn site, Mn is bonded in a 6-coordinate geometry to six Ge atoms. There are a spread of Mn–Ge bond distances ranging from 2.41–2.69 Å. In the third Mn site, Mn is bonded in a 6-coordinate geometry to six Ge atoms. There are a spread of Mn–Ge bond distances ranging from 2.57–2.61 Å. In the fourth Mn site, Mn is bonded to seven Ge atoms to form distorted MnGe7 pentagonal bipyramids that share corners with two equivalent MnGe7 pentagonal bipyramids, corners with five NbGe7 pentagonal bipyramids, and an edgeedge with one NbGe7 pentagonal bipyramid. There are a spread of Mn–Ge bond distances ranging from 2.51–2.76 Å. In the fifth Mn site, Mn is bonded in a 6-coordinate geometry to six Ge atoms. There are a spread of Mn–Ge bond distances ranging from 2.45–2.71 Å. In the sixth Mn site, Mn is bonded in a 4-coordinate geometry to six Ge atoms. There are a spread of Mn–Ge bond distances ranging from 2.48–2.85 Å. In the seventh Mn site, Mn is bonded in a 4-coordinate geometry to six Ge atoms. There are a spread of Mn–Ge bond distances ranging from 2.48–2.91 Å. There are seven inequivalent Ge sites. In the first Ge site, Ge is bonded in a 10-coordinate geometry to one Nb and nine Mn atoms. In the second Ge site, Ge is bonded in a 9-coordinate geometry to three Nb and six Mn atoms. In the third Ge site, Ge is bonded in a 9-coordinate geometry to nine Mn atoms. In the fourth Ge site, Ge is bonded in a 9-coordinate geometry to two Nb, five Mn, and two equivalent Ge atoms. There are one shorter (2.50 Å) and one longer (2.58 Å) Ge–Ge bond lengths. In the fifth Ge site, Ge is bonded in a 9-coordinate geometry to four Nb and five Mn atoms. In the sixth Ge site, Ge is bonded in a 8-coordinate geometry to one Nb and seven Mn atoms. In the seventh Ge site, Ge is bonded in a 8-coordinate geometry to one Nb and seven Mn atoms.