Materials Data on Li2CuSiO4 by Materials Project

Li2CuSiO4 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to four O2- atoms to form LiO4 tetrahedra that share corners with two equivalent LiO4 tetrahedra and corners with four equivalent SiO4 tetrahedra. There is three shorter (1.98 Å) and one longer (2.00 Å) Li–O bond length. In the second Li1+ site, Li1+ is bonded in a see-saw-like geometry to four O2- atoms. There are a spread of Li–O bond distances ranging from 1.94–2.21 Å. Cu2+ is bonded in a distorted rectangular see-saw-like geometry to four O2- atoms. There are a spread of Cu–O bond distances ranging from 1.89–2.14 Å. Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with four equivalent LiO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.61–1.68 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded to three Li1+ and one Si4+ atom to form distorted OLi3Si tetrahedra that share corners with four OLi3Si tetrahedra, corners with two equivalent OLi2CuSi trigonal pyramids, an edgeedge with one OLi2CuSi tetrahedra, and an edgeedge with one OLi2CuSi trigonal pyramid. In the second O2- site, O2- is bonded to two Li1+, one Cu2+, and one Si4+ atom to form distorted OLi2CuSi tetrahedra that share corners with two equivalent OLi3Si tetrahedra, corners with four equivalent OLi2CuSi trigonal pyramids, and an edgeedge with one OLi3Si tetrahedra. In the third O2- site, O2- is bonded to two Li1+, one Cu2+, and one Si4+ atom to form a mixture of distorted corner and edge-sharing OLi2CuSi trigonal pyramids. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to one Li1+, two equivalent Cu2+, and one Si4+ atom.