Materials Data on NaSmSiO4 by Materials Project
NaSmSiO4 crystallizes in the tetragonal I4/m space group. The structure is three-dimensional. Na1+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Na–O bond distances ranging from 2.42–2.77 Å. Sm3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Sm–O bond distances ranging from 2.33–2.87 Å. Si4+ is bonded in a tetrahedral geometry to four O2- atoms. There are a spread of Si–O bond distances ranging from 1.63–1.67 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to one Na1+, two equivalent Sm3+, and one Si4+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, three equivalent Sm3+, and one Si4+ atom. In the third O2- site, O2- is bonded to four equivalent Na1+, one Sm3+, and one Si4+ atom to form a mixture of distorted edge and corner-sharing ONa4SmSi octahedra. The corner-sharing octahedral tilt angles are 11°.