Mg3SiO5F is beta indium sulfide-derived structured and crystallizes in the orthorhombic Pna2_1 space group. There are three inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one F(1) atom to form MgO5F octahedra that share corners with two equivalent Mg(2)O5F octahedra, corners with four equivalent Mg(3)O5F octahedra, corners with two equivalent Si(1)O4 tetrahedra,  an edgeedge with one Mg(3)O5F octahedra, edges with two equivalent Mg(2)O5F octahedra, and  an edgeedge with one Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 47-59°. In the second Mg site, Mg(2) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one F(1) atom to form MgO5F octahedra that share corners with two equivalent Mg(1)O5F octahedra, corners with four equivalent Mg(3)O5F octahedra, corners with two equivalent Si(1)O4 tetrahedra,  an edgeedge with one Mg(3)O5F octahedra, edges with two equivalent Mg(1)O5F octahedra, and  an edgeedge with one Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 45-59°. In the third Mg site, Mg(3) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one F(1) atom to form MgO5F octahedra that share corners with four equivalent Mg(1)O5F octahedra, corners with four equivalent Mg(2)O5F octahedra, corners with two equivalent Si(1)O4 tetrahedra,  an edgeedge with one Mg(1)O5F octahedra,  an edgeedge with one Mg(2)O5F octahedra, and  an edgeedge with one Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 45-59°. Si(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form SiO4 tetrahedra that share corners with two equivalent Mg(1)O5F octahedra, corners with two equivalent Mg(2)O5F octahedra, corners with two equivalent Mg(3)O5F octahedra,  an edgeedge with one Mg(1)O5F octahedra,  an edgeedge with one Mg(2)O5F octahedra, and  an edgeedge with one Mg(3)O5F octahedra. The corner-sharing octahedral tilt angles range from 55-61°. There are five inequivalent O sites. In the first O site, O(5) is bonded in a distorted trigonal planar geometry to one Mg(1), one Mg(2), and one Mg(3) atom. In the second O site, O(1) is bonded in a 4-coordinate geometry to one Mg(1), one Mg(2), one Mg(3), and one Si(1) atom. In the third O site, O(2) is bonded to one Mg(1), one Mg(2), one Mg(3), and one Si(1) atom to form a mixture of distorted corner and edge-sharing OMg3Si trigonal pyramids. In the fourth O site, O(3) is bonded to one Mg(1), one Mg(2), one Mg(3), and one Si(1) atom to form a mixture of distorted corner and edge-sharing OMg3Si trigonal pyramids. In the fifth O site, O(4) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Mg(2), one Mg(3), and one Si(1) atom. F(1) is bonded in a distorted trigonal planar geometry to one Mg(1), one Mg(2), and one Mg(3) atom.
Mg3SiO5F is beta indium sulfide-derived structured and crystallizes in the orthorhombic Pna2_1 space group. There are three inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one F(1) atom to form MgO5F octahedra that share corners with two equivalent Mg(2)O5F octahedra, corners with four equivalent Mg(3)O5F octahedra, corners with two equivalent Si(1)O4 tetrahedra,  an edgeedge with one Mg(3)O5F octahedra, edges with two equivalent Mg(2)O5F octahedra, and  an edgeedge with one Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 47-59°. The Mg(1)-O(1) bond length is 2.14 Å. The Mg(1)-O(2) bond length is 2.13 Å. The Mg(1)-O(3) bond length is 2.02 Å. The Mg(1)-O(4) bond length is 2.25 Å. The Mg(1)-O(5) bond length is 2.06 Å. The Mg(1)-F(1) bond length is 2.09 Å. In the second Mg site, Mg(2) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one F(1) atom to form MgO5F octahedra that share corners with two equivalent Mg(1)O5F octahedra, corners with four equivalent Mg(3)O5F octahedra, corners with two equivalent Si(1)O4 tetrahedra,  an edgeedge with one Mg(3)O5F octahedra, edges with two equivalent Mg(1)O5F octahedra, and  an edgeedge with one Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 45-59°. The Mg(2)-O(1) bond length is 2.09 Å. The Mg(2)-O(2) bond length is 2.03 Å. The Mg(2)-O(3) bond length is 2.16 Å. The Mg(2)-O(4) bond length is 2.21 Å. The Mg(2)-O(5) bond length is 2.06 Å. The Mg(2)-F(1) bond length is 2.04 Å. In the third Mg site, Mg(3) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one F(1) atom to form MgO5F octahedra that share corners with four equivalent Mg(1)O5F octahedra, corners with four equivalent Mg(2)O5F octahedra, corners with two equivalent Si(1)O4 tetrahedra,  an edgeedge with one Mg(1)O5F octahedra,  an edgeedge with one Mg(2)O5F octahedra, and  an edgeedge with one Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 45-59°. The Mg(3)-O(1) bond length is 2.29 Å. The Mg(3)-O(2) bond length is 2.20 Å. The Mg(3)-O(3) bond length is 2.16 Å. The Mg(3)-O(4) bond length is 2.06 Å. The Mg(3)-O(5) bond length is 2.07 Å. The Mg(3)-F(1) bond length is 2.03 Å. Si(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form SiO4 tetrahedra that share corners with two equivalent Mg(1)O5F octahedra, corners with two equivalent Mg(2)O5F octahedra, corners with two equivalent Mg(3)O5F octahedra,  an edgeedge with one Mg(1)O5F octahedra,  an edgeedge with one Mg(2)O5F octahedra, and  an edgeedge with one Mg(3)O5F octahedra. The corner-sharing octahedral tilt angles range from 55-61°. The Si(1)-O(1) bond length is 1.63 Å. The Si(1)-O(2) bond length is 1.66 Å. The Si(1)-O(3) bond length is 1.66 Å. The Si(1)-O(4) bond length is 1.66 Å. There are five inequivalent O sites. In the first O site, O(5) is bonded in a distorted trigonal planar geometry to one Mg(1), one Mg(2), and one Mg(3) atom. In the second O site, O(1) is bonded in a 4-coordinate geometry to one Mg(1), one Mg(2), one Mg(3), and one Si(1) atom. In the third O site, O(2) is bonded to one Mg(1), one Mg(2), one Mg(3), and one Si(1) atom to form a mixture of distorted corner and edge-sharing OMg3Si trigonal pyramids. In the fourth O site, O(3) is bonded to one Mg(1), one Mg(2), one Mg(3), and one Si(1) atom to form a mixture of distorted corner and edge-sharing OMg3Si trigonal pyramids. In the fifth O site, O(4) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Mg(2), one Mg(3), and one Si(1) atom. F(1) is bonded in a distorted trigonal planar geometry to one Mg(1), one Mg(2), and one Mg(3) atom.