Materials Data on Na2SrAl4(SiO4)4 by Materials Project
Na2SrAl4(SiO4)4 crystallizes in the orthorhombic Iba2 space group. The structure is three-dimensional. Na1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Na–O bond distances ranging from 2.37–2.76 Å. Sr2+ is bonded in a 10-coordinate geometry to ten O2- atoms. There are a spread of Sr–O bond distances ranging from 2.68–3.01 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 four SiO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.74–1.77 Å. In the second Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with four SiO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.75–1.78 Å. 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 four AlO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.62–1.65 Å. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with four AlO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.62–1.65 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to one Na1+, one Sr2+, one Al3+, and one Si4+ atom. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Na1+, one Al3+, and one Si4+ atom. In the third O2- site, O2- is bonded in a bent 120 degrees geometry to one Sr2+, 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 distorted linear geometry to one Sr2+, one Al3+, and one Si4+ atom. In the sixth O2- site, O2- is bonded in a 2-coordinate geometry to one Na1+, one Sr2+, 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 distorted bent 120 degrees geometry to one Sr2+, one Al3+, and one Si4+ atom.