Materials Data on Al2O3 by Materials Project

Abstract

Al2O3 is Corundum-like structured and crystallizes in the orthorhombic Pbca space group. The structure is three-dimensional. there are two inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to six O2- atoms to form a mixture of face, edge, and corner-sharing AlO6 octahedra. The corner-sharing octahedra tilt angles range from 47–61°. There are a spread of Al–O bond distances ranging from 1.85–1.99 Å. In the second Al3+ site, Al3+ is bonded to six O2- atoms to form a mixture of face, edge, and corner-sharing AlO6 octahedra. The corner-sharing octahedra tilt angles range from 48–70°. There are a spread of Al–O bond distances ranging from 1.88–2.05 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded to four Al3+ atoms to form a mixture of distorted edge and corner-sharing OAl4 tetrahedra. In the second O2- site, O2- is bonded to four Al3+ atoms to form a mixture of distorted edge and corner-sharing OAl4 trigonal pyramids. In the third O2- site, O2- is bonded to four Al3+ atoms to form a mixture of distorted edge and corner-sharing OAl4 trigonal pyramids.