YAlO3 crystallizes in the orthorhombic Cmcm space group. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded in a distorted body-centered cubic geometry to two equivalent O(1), two equivalent O(4), and four equivalent O(2) atoms. In the second Y site, Y(2) is bonded in a body-centered cubic geometry to two equivalent O(3), two equivalent O(4), and four equivalent O(2) atoms. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to one O(1), one O(3), and two equivalent O(2) atoms to form corner-sharing AlO4 tetrahedra. In the second Al site, Al(2) is bonded to two equivalent O(1) and two equivalent O(4) atoms to form corner-sharing AlO4 tetrahedra. There are four inequivalent O sites. In the first O site, O(3) is bonded in a distorted bent 120 degrees geometry to two equivalent Y(2) and two equivalent Al(1) atoms. In the second O site, O(4) is bonded to one Y(2), two equivalent Y(1), and one Al(2) atom to form a mixture of distorted edge and corner-sharing OY3Al tetrahedra. In the third O site, O(1) is bonded in a distorted bent 120 degrees geometry to two equivalent Y(1), one Al(1), and one Al(2) atom. In the fourth O site, O(2) is bonded to one Y(2), two equivalent Y(1), and one Al(1) atom to form a mixture of distorted edge and corner-sharing OY3Al tetrahedra.
YAlO3 crystallizes in the orthorhombic Cmcm space group. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded in a distorted body-centered cubic geometry to two equivalent O(1), two equivalent O(4), and four equivalent O(2) atoms. Both Y(1)-O(1) bond lengths are 2.59 Å. Both Y(1)-O(4) bond lengths are 2.50 Å. There are two shorter (2.25 Å) and two longer (2.48 Å) Y(1)-O(2) bond lengths. In the second Y site, Y(2) is bonded in a body-centered cubic geometry to two equivalent O(3), two equivalent O(4), and four equivalent O(2) atoms. Both Y(2)-O(3) bond lengths are 2.58 Å. Both Y(2)-O(4) bond lengths are 2.26 Å. All Y(2)-O(2) bond lengths are 2.49 Å. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to one O(1), one O(3), and two equivalent O(2) atoms to form corner-sharing AlO4 tetrahedra. The Al(1)-O(1) bond length is 1.78 Å. The Al(1)-O(3) bond length is 1.78 Å. Both Al(1)-O(2) bond lengths are 1.74 Å. In the second Al site, Al(2) is bonded to two equivalent O(1) and two equivalent O(4) atoms to form corner-sharing AlO4 tetrahedra. Both Al(2)-O(1) bond lengths are 1.78 Å. Both Al(2)-O(4) bond lengths are 1.77 Å. There are four inequivalent O sites. In the first O site, O(3) is bonded in a distorted bent 120 degrees geometry to two equivalent Y(2) and two equivalent Al(1) atoms. In the second O site, O(4) is bonded to one Y(2), two equivalent Y(1), and one Al(2) atom to form a mixture of distorted edge and corner-sharing OY3Al tetrahedra. In the third O site, O(1) is bonded in a distorted bent 120 degrees geometry to two equivalent Y(1), one Al(1), and one Al(2) atom. In the fourth O site, O(2) is bonded to one Y(2), two equivalent Y(1), and one Al(1) atom to form a mixture of distorted edge and corner-sharing OY3Al tetrahedra.