LiLaTa2O7 crystallizes in the tetragonal I-4m2 space group. Li(1) is bonded to four equivalent O(3) atoms to form corner-sharing LiO4 tetrahedra. La(1) is bonded to four equivalent O(1), four equivalent O(2), and four equivalent O(4) atoms to form a mixture of face and corner-sharing LaO12 cuboctahedra. Ta(1) is bonded in a 6-coordinate geometry to one O(3), one O(4), two equivalent O(1), and two equivalent O(2) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 150 degrees geometry to two equivalent La(1) and two equivalent Ta(1) atoms. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to two equivalent La(1) and two equivalent Ta(1) atoms. In the third O site, O(3) is bonded in a trigonal planar geometry to two equivalent Li(1) and one Ta(1) atom. In the fourth O site, O(4) is bonded to four equivalent La(1) and two equivalent Ta(1) atoms to form a mixture of edge and corner-sharing OLa4Ta2 octahedra. The corner-sharing octahedra are not tilted.
LiLaTa2O7 crystallizes in the tetragonal I-4m2 space group. Li(1) is bonded to four equivalent O(3) atoms to form corner-sharing LiO4 tetrahedra. All Li(1)-O(3) bond lengths are 2.22 Å. La(1) is bonded to four equivalent O(1), four equivalent O(2), and four equivalent O(4) atoms to form a mixture of face and corner-sharing LaO12 cuboctahedra. All La(1)-O(1) bond lengths are 2.70 Å. All La(1)-O(2) bond lengths are 2.68 Å. All La(1)-O(4) bond lengths are 2.75 Å. Ta(1) is bonded in a 6-coordinate geometry to one O(3), one O(4), two equivalent O(1), and two equivalent O(2) atoms. The Ta(1)-O(3) bond length is 1.81 Å. The Ta(1)-O(4) bond length is 2.31 Å. Both Ta(1)-O(1) bond lengths are 2.00 Å. Both Ta(1)-O(2) bond lengths are 2.00 Å. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 150 degrees geometry to two equivalent La(1) and two equivalent Ta(1) atoms. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to two equivalent La(1) and two equivalent Ta(1) atoms. In the third O site, O(3) is bonded in a trigonal planar geometry to two equivalent Li(1) and one Ta(1) atom. In the fourth O site, O(4) is bonded to four equivalent La(1) and two equivalent Ta(1) atoms to form a mixture of edge and corner-sharing OLa4Ta2 octahedra. The corner-sharing octahedra are not tilted.