Li2Si3O7 crystallizes in the orthorhombic Pbcm space group. Li(1) is bonded to one O(2) and three equivalent O(1) atoms to form LiO4 tetrahedra that share corners with two equivalent Li(1)O4 tetrahedra, corners with five equivalent Si(1)O4 tetrahedra, and edges with two equivalent Li(1)O4 tetrahedra. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(3), and two equivalent O(2) atoms to form SiO4 tetrahedra that share  a cornercorner with one Si(2)O4 tetrahedra, corners with two equivalent Si(1)O4 tetrahedra, and corners with five equivalent Li(1)O4 tetrahedra. In the second Si site, Si(2) is bonded to two equivalent O(3) and two equivalent O(4) atoms to form corner-sharing SiO4 tetrahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded to three equivalent Li(1) and one Si(1) atom to form a mixture of distorted corner and edge-sharing OLi3Si trigonal pyramids. In the second O site, O(2) is bonded in a trigonal planar geometry to one Li(1) and two equivalent Si(1) atoms. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(2) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to two equivalent Si(2) atoms.
Li2Si3O7 crystallizes in the orthorhombic Pbcm space group. Li(1) is bonded to one O(2) and three equivalent O(1) atoms to form LiO4 tetrahedra that share corners with two equivalent Li(1)O4 tetrahedra, corners with five equivalent Si(1)O4 tetrahedra, and edges with two equivalent Li(1)O4 tetrahedra. The Li(1)-O(2) bond length is 2.07 Å. There are a spread of Li(1)-O(1) bond distances ranging from 1.95-1.99 Å. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(3), and two equivalent O(2) atoms to form SiO4 tetrahedra that share  a cornercorner with one Si(2)O4 tetrahedra, corners with two equivalent Si(1)O4 tetrahedra, and corners with five equivalent Li(1)O4 tetrahedra. The Si(1)-O(1) bond length is 1.60 Å. The Si(1)-O(3) bond length is 1.63 Å. There is one shorter (1.67 Å) and one longer (1.68 Å) Si(1)-O(2) bond length. In the second Si site, Si(2) is bonded to two equivalent O(3) and two equivalent O(4) atoms to form corner-sharing SiO4 tetrahedra. Both Si(2)-O(3) bond lengths are 1.62 Å. Both Si(2)-O(4) bond lengths are 1.63 Å. There are four inequivalent O sites. In the first O site, O(1) is bonded to three equivalent Li(1) and one Si(1) atom to form a mixture of distorted corner and edge-sharing OLi3Si trigonal pyramids. In the second O site, O(2) is bonded in a trigonal planar geometry to one Li(1) and two equivalent Si(1) atoms. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(2) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to two equivalent Si(2) atoms.