Li2La3Ti2Nb2O13 crystallizes in the tetragonal I4/mmm space group. Li(1) is bonded in a distorted square co-planar geometry to four equivalent O(5) atoms. There are two inequivalent La sites. In the first La site, La(1) is bonded to four equivalent O(1) and eight equivalent O(2) atoms to form LaO12 cuboctahedra that share corners with four equivalent La(1)O12 cuboctahedra, corners with eight equivalent La(2)O12 cuboctahedra, faces with two equivalent La(2)O12 cuboctahedra, faces with four equivalent La(1)O12 cuboctahedra, and faces with eight equivalent Ti(1)O6 octahedra. In the second La site, La(2) is bonded to four equivalent O(2), four equivalent O(3), and four equivalent O(4) atoms to form LaO12 cuboctahedra that share corners with four equivalent La(1)O12 cuboctahedra, corners with four equivalent La(2)O12 cuboctahedra,  a faceface with one La(1)O12 cuboctahedra, faces with four equivalent La(2)O12 cuboctahedra, faces with four equivalent Ti(1)O6 octahedra, and faces with four equivalent Nb(1)O6 octahedra. Ti(1) is bonded to one O(1), one O(3), and four equivalent O(2) atoms to form TiO6 octahedra that share  a cornercorner with one Nb(1)O6 octahedra, corners with five equivalent Ti(1)O6 octahedra, faces with four equivalent La(1)O12 cuboctahedra, and faces with four equivalent La(2)O12 cuboctahedra. The corner-sharing octahedra are not tilted. Nb(1) is bonded to one O(3), one O(5), and four equivalent O(4) atoms to form NbO6 octahedra that share  a cornercorner with one Ti(1)O6 octahedra, corners with four equivalent Nb(1)O6 octahedra, and faces with four equivalent La(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-17°. There are five inequivalent O sites. In the first O site, O(1) is bonded in a distorted linear geometry to four equivalent La(1) and two equivalent Ti(1) atoms. In the second O site, O(2) is bonded in a distorted linear geometry to two equivalent La(1), two equivalent La(2), and two equivalent Ti(1) atoms. In the third O site, O(3) is bonded in a distorted linear geometry to four equivalent La(2), one Ti(1), and one Nb(1) atom. In the fourth O site, O(4) is bonded in a 2-coordinate geometry to two equivalent La(2) and two equivalent Nb(1) atoms. In the fifth O site, O(5) is bonded to four equivalent Li(1) and one Nb(1) atom to form a mixture of distorted corner and edge-sharing OLi4Nb trigonal bipyramids.
Li2La3Ti2Nb2O13 crystallizes in the tetragonal I4/mmm space group. Li(1) is bonded in a distorted square co-planar geometry to four equivalent O(5) atoms. All Li(1)-O(5) bond lengths are 2.06 Å. There are two inequivalent La sites. In the first La site, La(1) is bonded to four equivalent O(1) and eight equivalent O(2) atoms to form LaO12 cuboctahedra that share corners with four equivalent La(1)O12 cuboctahedra, corners with eight equivalent La(2)O12 cuboctahedra, faces with two equivalent La(2)O12 cuboctahedra, faces with four equivalent La(1)O12 cuboctahedra, and faces with eight equivalent Ti(1)O6 octahedra. All La(1)-O(1) bond lengths are 2.83 Å. All La(1)-O(2) bond lengths are 2.80 Å. In the second La site, La(2) is bonded to four equivalent O(2), four equivalent O(3), and four equivalent O(4) atoms to form LaO12 cuboctahedra that share corners with four equivalent La(1)O12 cuboctahedra, corners with four equivalent La(2)O12 cuboctahedra,  a faceface with one La(1)O12 cuboctahedra, faces with four equivalent La(2)O12 cuboctahedra, faces with four equivalent Ti(1)O6 octahedra, and faces with four equivalent Nb(1)O6 octahedra. All La(2)-O(2) bond lengths are 2.88 Å. All La(2)-O(3) bond lengths are 2.83 Å. All La(2)-O(4) bond lengths are 2.65 Å. Ti(1) is bonded to one O(1), one O(3), and four equivalent O(2) atoms to form TiO6 octahedra that share  a cornercorner with one Nb(1)O6 octahedra, corners with five equivalent Ti(1)O6 octahedra, faces with four equivalent La(1)O12 cuboctahedra, and faces with four equivalent La(2)O12 cuboctahedra. The corner-sharing octahedra are not tilted. The Ti(1)-O(1) bond length is 1.96 Å. The Ti(1)-O(3) bond length is 1.97 Å. All Ti(1)-O(2) bond lengths are 2.00 Å. Nb(1) is bonded to one O(3), one O(5), and four equivalent O(4) atoms to form NbO6 octahedra that share  a cornercorner with one Ti(1)O6 octahedra, corners with four equivalent Nb(1)O6 octahedra, and faces with four equivalent La(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-17°. The Nb(1)-O(3) bond length is 2.12 Å. The Nb(1)-O(5) bond length is 1.90 Å. All Nb(1)-O(4) bond lengths are 2.03 Å. There are five inequivalent O sites. In the first O site, O(1) is bonded in a distorted linear geometry to four equivalent La(1) and two equivalent Ti(1) atoms. In the second O site, O(2) is bonded in a distorted linear geometry to two equivalent La(1), two equivalent La(2), and two equivalent Ti(1) atoms. In the third O site, O(3) is bonded in a distorted linear geometry to four equivalent La(2), one Ti(1), and one Nb(1) atom. In the fourth O site, O(4) is bonded in a 2-coordinate geometry to two equivalent La(2) and two equivalent Nb(1) atoms. In the fifth O site, O(5) is bonded to four equivalent Li(1) and one Nb(1) atom to form a mixture of distorted corner and edge-sharing OLi4Nb trigonal bipyramids.