Sr2SiO4 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms. In the second Sr site, Sr(2) is bonded in a 8-coordinate geometry to one O(4), two equivalent O(1), two equivalent O(2), and three equivalent O(3) atoms. Si(1) is bonded in a tetrahedral geometry to one O(1), one O(2), one O(3), and one O(4) atom. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to two equivalent Sr(1), two equivalent Sr(2), and one Si(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to two equivalent Sr(1), two equivalent Sr(2), and one Si(1) atom. In the third O site, O(3) is bonded in a 1-coordinate geometry to two equivalent Sr(1), three equivalent Sr(2), and one Si(1) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Sr(2), two equivalent Sr(1), and one Si(1) atom.
Sr2SiO4 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms. There is one shorter (2.53 Å) and one longer (2.56 Å) Sr(1)-O(1) bond length. There is one shorter (2.54 Å) and one longer (2.70 Å) Sr(1)-O(2) bond length. There is one shorter (2.62 Å) and one longer (2.64 Å) Sr(1)-O(3) bond length. There is one shorter (2.60 Å) and one longer (2.77 Å) Sr(1)-O(4) bond length. In the second Sr site, Sr(2) is bonded in a 8-coordinate geometry to one O(4), two equivalent O(1), two equivalent O(2), and three equivalent O(3) atoms. The Sr(2)-O(4) bond length is 2.40 Å. There is one shorter (2.73 Å) and one longer (2.95 Å) Sr(2)-O(1) bond length. There is one shorter (2.63 Å) and one longer (2.75 Å) Sr(2)-O(2) bond length. There are a spread of Sr(2)-O(3) bond distances ranging from 2.56-3.13 Å. Si(1) is bonded in a tetrahedral geometry to one O(1), one O(2), one O(3), and one O(4) atom. The Si(1)-O(1) bond length is 1.63 Å. The Si(1)-O(2) bond length is 1.64 Å. The Si(1)-O(3) bond length is 1.65 Å. The Si(1)-O(4) bond length is 1.62 Å. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to two equivalent Sr(1), two equivalent Sr(2), and one Si(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to two equivalent Sr(1), two equivalent Sr(2), and one Si(1) atom. In the third O site, O(3) is bonded in a 1-coordinate geometry to two equivalent Sr(1), three equivalent Sr(2), and one Si(1) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Sr(2), two equivalent Sr(1), and one Si(1) atom.