SrSi crystallizes in the orthorhombic Immm space group. There are five inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 7-coordinate geometry to two equivalent Si(2), two equivalent Si(3), and three equivalent Si(1) atoms. In the second Sr site, Sr(2) is bonded in a 8-coordinate geometry to four equivalent Si(1) and four equivalent Si(2) atoms. In the third Sr site, Sr(3) is bonded to four equivalent Si(3) and eight equivalent Si(2) atoms to form distorted SrSi12 cuboctahedra that share corners with four equivalent Sr(4)Si5 square pyramids and faces with two equivalent Sr(3)Si12 cuboctahedra. In the fourth Sr site, Sr(4) is bonded to one Si(3) and four equivalent Si(1) atoms to form distorted SrSi5 square pyramids that share corners with two equivalent Sr(3)Si12 cuboctahedra and edges with two equivalent Sr(4)Si5 square pyramids. In the fifth Sr site, Sr(5) is bonded in a square co-planar geometry to four equivalent Si(1) atoms. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to one Sr(5), two equivalent Sr(2), two equivalent Sr(4), three equivalent Sr(1), and one Si(2) atom. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to two equivalent Sr(1), two equivalent Sr(2), two equivalent Sr(3), one Si(1), one Si(2), and one Si(3) atom. In the third Si site, Si(3) is bonded in a 9-coordinate geometry to one Sr(4), two equivalent Sr(3), four equivalent Sr(1), and two equivalent Si(2) atoms.
SrSi crystallizes in the orthorhombic Immm space group. There are five inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 7-coordinate geometry to two equivalent Si(2), two equivalent Si(3), and three equivalent Si(1) atoms. Both Sr(1)-Si(2) bond lengths are 3.24 Å. Both Sr(1)-Si(3) bond lengths are 3.33 Å. There is one shorter (3.30 Å) and two longer (3.31 Å) Sr(1)-Si(1) bond lengths. In the second Sr site, Sr(2) is bonded in a 8-coordinate geometry to four equivalent Si(1) and four equivalent Si(2) atoms. All Sr(2)-Si(1) bond lengths are 3.37 Å. All Sr(2)-Si(2) bond lengths are 3.23 Å. In the third Sr site, Sr(3) is bonded to four equivalent Si(3) and eight equivalent Si(2) atoms to form distorted SrSi12 cuboctahedra that share corners with four equivalent Sr(4)Si5 square pyramids and faces with two equivalent Sr(3)Si12 cuboctahedra. All Sr(3)-Si(3) bond lengths are 3.51 Å. All Sr(3)-Si(2) bond lengths are 3.37 Å. In the fourth Sr site, Sr(4) is bonded to one Si(3) and four equivalent Si(1) atoms to form distorted SrSi5 square pyramids that share corners with two equivalent Sr(3)Si12 cuboctahedra and edges with two equivalent Sr(4)Si5 square pyramids. The Sr(4)-Si(3) bond length is 3.41 Å. All Sr(4)-Si(1) bond lengths are 3.43 Å. In the fifth Sr site, Sr(5) is bonded in a square co-planar geometry to four equivalent Si(1) atoms. All Sr(5)-Si(1) bond lengths are 3.29 Å. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to one Sr(5), two equivalent Sr(2), two equivalent Sr(4), three equivalent Sr(1), and one Si(2) atom. The Si(1)-Si(2) bond length is 2.41 Å. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to two equivalent Sr(1), two equivalent Sr(2), two equivalent Sr(3), one Si(1), one Si(2), and one Si(3) atom. The Si(2)-Si(2) bond length is 2.45 Å. The Si(2)-Si(3) bond length is 2.41 Å. In the third Si site, Si(3) is bonded in a 9-coordinate geometry to one Sr(4), two equivalent Sr(3), four equivalent Sr(1), and two equivalent Si(2) atoms.