LiCu3(SiO3)2 crystallizes in the monoclinic C2/m space group. Li(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form LiO6 octahedra that share edges with six equivalent Si(1)O6 octahedra. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a linear geometry to two equivalent O(1) atoms. In the second Cu site, Cu(2) is bonded in a linear geometry to two equivalent O(2) atoms. Si(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form SiO6 octahedra that share edges with three equivalent Li(1)O6 octahedra and edges with three equivalent Si(1)O6 octahedra. There are two inequivalent O sites. In the first O site, O(1) is bonded to one Li(1), one Cu(1), and two equivalent Si(1) atoms to form a mixture of corner and edge-sharing OLiCuSi2 trigonal pyramids. In the second O site, O(2) is bonded to one Li(1), one Cu(2), and two equivalent Si(1) atoms to form a mixture of corner and edge-sharing OLiCuSi2 trigonal pyramids.
LiCu3(SiO3)2 crystallizes in the monoclinic C2/m space group. Li(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form LiO6 octahedra that share edges with six equivalent Si(1)O6 octahedra. Both Li(1)-O(2) bond lengths are 2.04 Å. All Li(1)-O(1) bond lengths are 2.03 Å. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a linear geometry to two equivalent O(1) atoms. Both Cu(1)-O(1) bond lengths are 1.89 Å. In the second Cu site, Cu(2) is bonded in a linear geometry to two equivalent O(2) atoms. Both Cu(2)-O(2) bond lengths are 1.88 Å. Si(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form SiO6 octahedra that share edges with three equivalent Li(1)O6 octahedra and edges with three equivalent Si(1)O6 octahedra. Both Si(1)-O(2) bond lengths are 1.81 Å. All Si(1)-O(1) bond lengths are 1.81 Å. There are two inequivalent O sites. In the first O site, O(1) is bonded to one Li(1), one Cu(1), and two equivalent Si(1) atoms to form a mixture of corner and edge-sharing OLiCuSi2 trigonal pyramids. In the second O site, O(2) is bonded to one Li(1), one Cu(2), and two equivalent Si(1) atoms to form a mixture of corner and edge-sharing OLiCuSi2 trigonal pyramids.