Materials Data on CaAl2O8 by Materials Project
CaAl2O8 crystallizes in the trigonal P3 space group. The structure is three-dimensional. there are two inequivalent Ca sites. In the first Ca site, Ca is bonded in a 6-coordinate geometry to six O atoms. There are a spread of Ca–O bond distances ranging from 2.35–2.67 Å. In the second Ca site, Ca is bonded in a 5-coordinate geometry to five O atoms. There are a spread of Ca–O bond distances ranging from 2.25–2.37 Å. There are four inequivalent Al sites. In the first Al site, Al is bonded in a distorted octahedral geometry to six O atoms. There are a spread of Al–O bond distances ranging from 1.81–1.99 Å. In the second Al site, Al is bonded to six O atoms to form edge-sharing AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.83–1.94 Å. In the third Al site, Al is bonded to six O atoms to form edge-sharing AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.86–1.92 Å. In the fourth Al site, Al is bonded in a 6-coordinate geometry to six O atoms. There are a spread of Al–O bond distances ranging from 1.84–2.15 Å. There are sixteen inequivalent O sites. In the first O site, O is bonded in a distorted T-shaped geometry to one Ca and two Al atoms. In the second O site, O is bonded in a single-bond geometry to one Al atom. In the third O site, O is bonded in a T-shaped geometry to one Ca and two Al atoms. In the fourth O site, O is bonded in a single-bond geometry to one Al atom. In the fifth O site, O is bonded in a water-like geometry to two Al atoms. In the sixth O site, O is bonded in a bent 120 degrees geometry to two Al atoms. In the seventh O site, O is bonded in a single-bond geometry to one Al atom. In the eighth O site, O is bonded in a distorted trigonal non-coplanar geometry to two Ca and one Al atom. In the ninth O site, O is bonded in a distorted T-shaped geometry to one Ca and two Al atoms. In the tenth O site, O is bonded in a distorted T-shaped geometry to one Ca and two Al atoms. In the eleventh O site, O is bonded in a bent 150 degrees geometry to one Ca and one Al atom. In the twelfth O site, O is bonded in a single-bond geometry to one Al atom. In the thirteenth O site, O is bonded in a distorted trigonal non-coplanar geometry to two Ca and one Al atom. In the fourteenth O site, O is bonded in a water-like geometry to two Al atoms. In the fifteenth O site, O is bonded in a 2-coordinate geometry to two Ca and one Al atom. In the sixteenth O site, O is bonded in a bent 120 degrees geometry to two Al atoms.