Materials Data on Al2Si2PbO8 by Materials Project

Abstract

PbAl2Si2O8 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. 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 is two shorter (1.74 Å) and two longer (1.78 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 four SiO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.74–1.77 Å. Pb2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Pb–O bond distances ranging from 2.50–3.11 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 1.62–1.66 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 is two shorter (1.63 Å) and two longer (1.65 Å) Si–O bond length. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to one Al3+, one Pb2+, and one Si4+ atom. In the second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Al3+, one Pb2+, and one Si4+ atom. In the third O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Al3+, two equivalent Pb2+, and one Si4+ atom. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Al3+, one Pb2+, and one Si4+ atom. In the fifth O2- site, O2- is bonded in a bent 150 degrees geometry to one Al3+, one Pb2+, and one Si4+ atom. In the sixth O2- site, O2- is bonded in a bent 150 degrees geometry to one Al3+, one Pb2+, and one Si4+ atom. In the seventh O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Al3+, one Pb2+, and one Si4+ atom. In the eighth O2- site, O2- is bonded in a bent 120 degrees geometry to one Al3+ and one Si4+ atom.