Materials Data on NaAlSiO4 by Materials Project

Abstract

NaAlSiO4 crystallizes in the orthorhombic Pca2_1 space group. The structure is three-dimensional. there are two inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to four O2- atoms to form distorted NaO4 tetrahedra that share corners with four AlO4 tetrahedra and corners with four SiO4 tetrahedra. There are a spread of Na–O bond distances ranging from 2.37–2.46 Å. In the second Na1+ site, Na1+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Na–O bond distances ranging from 2.40–2.42 Å. There are two inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with two equivalent NaO4 tetrahedra and corners with four SiO4 tetrahedra. There is one shorter (1.76 Å) and three longer (1.77 Å) Al–O bond length. In the second Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with two equivalent NaO4 tetrahedra and corners with four SiO4 tetrahedra. There is one shorter (1.76 Å) and three longer (1.77 Å) Al–O bond length. There are two inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two equivalent NaO4 tetrahedra and corners with four AlO4 tetrahedra. There is one shorter (1.63 Å) and three longer (1.64 Å) Si–O bond length. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two equivalent NaO4 tetrahedra and corners with four AlO4 tetrahedra. All Si–O bond lengths are 1.64 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Na1+, one Al3+, and one Si4+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Al3+, and one Si4+ atom. In the third O2- site, O2- is bonded in a 2-coordinate geometry to one Na1+, one Al3+, and one Si4+ atom. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Al3+, and one Si4+ atom. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Al3+, and one Si4+ atom. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Al3+, and one Si4+ atom. In the seventh O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Al3+, and one Si4+ atom. In the eighth O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Al3+, and one Si4+ atom.