Materials Data on NaCaSiO4 by Materials Project
NaCaSiO4 crystallizes in the orthorhombic C222_1 space group. The structure is three-dimensional. Na is bonded in a 4-coordinate geometry to four O atoms. There are two shorter (2.34 Å) and two longer (2.48 Å) Na–O bond lengths. Ca is bonded to six O atoms to form CaO6 octahedra that share corners with six equivalent SiO4 tetrahedra and edges with two equivalent CaO6 octahedra. There are a spread of Ca–O bond distances ranging from 2.36–2.40 Å. Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with six equivalent CaO6 octahedra. The corner-sharing octahedra tilt angles range from 44–54°. There is two shorter (1.64 Å) and two longer (1.66 Å) Si–O bond length. There are two inequivalent O sites. In the first O site, O is bonded in a 1-coordinate geometry to one Na, two equivalent Ca, and one Si atom. In the second O site, O is bonded in a 3-coordinate geometry to one Na, one Ca, and one Si atom.