LiYMo3O8 crystallizes in the trigonal P3m1 space group. Li(1) is bonded to one O(1) and three equivalent O(4) atoms to form distorted LiO4 trigonal pyramids that share corners with three equivalent Y(1)O6 octahedra, corners with three equivalent Mo(1)O6 octahedra, and edges with three equivalent Mo(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 61-65°. Y(1) is bonded to three equivalent O(2) and three equivalent O(4) atoms to form YO6 octahedra that share corners with twelve equivalent Mo(1)O6 octahedra and corners with three equivalent Li(1)O4 trigonal pyramids. The corner-sharing octahedral tilt angles range from 50-53°. Mo(1) is bonded to one O(1), one O(3), two equivalent O(2), and two equivalent O(4) atoms to form MoO6 octahedra that share corners with four equivalent Y(1)O6 octahedra,  a cornercorner with one Li(1)O4 trigonal pyramid, edges with four equivalent Mo(1)O6 octahedra, and  an edgeedge with one Li(1)O4 trigonal pyramid. The corner-sharing octahedral tilt angles range from 50-53°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted tetrahedral geometry to one Li(1) and three equivalent Mo(1) atoms. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Y(1) and two equivalent Mo(1) atoms. In the third O site, O(3) is bonded in a distorted T-shaped geometry to three equivalent Mo(1) atoms. In the fourth O site, O(4) is bonded in a distorted rectangular see-saw-like geometry to one Li(1), one Y(1), and two equivalent Mo(1) atoms.
LiYMo3O8 crystallizes in the trigonal P3m1 space group. Li(1) is bonded to one O(1) and three equivalent O(4) atoms to form distorted LiO4 trigonal pyramids that share corners with three equivalent Y(1)O6 octahedra, corners with three equivalent Mo(1)O6 octahedra, and edges with three equivalent Mo(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 61-65°. The Li(1)-O(1) bond length is 1.77 Å. All Li(1)-O(4) bond lengths are 1.94 Å. Y(1) is bonded to three equivalent O(2) and three equivalent O(4) atoms to form YO6 octahedra that share corners with twelve equivalent Mo(1)O6 octahedra and corners with three equivalent Li(1)O4 trigonal pyramids. The corner-sharing octahedral tilt angles range from 50-53°. All Y(1)-O(2) bond lengths are 2.36 Å. All Y(1)-O(4) bond lengths are 2.37 Å. Mo(1) is bonded to one O(1), one O(3), two equivalent O(2), and two equivalent O(4) atoms to form MoO6 octahedra that share corners with four equivalent Y(1)O6 octahedra,  a cornercorner with one Li(1)O4 trigonal pyramid, edges with four equivalent Mo(1)O6 octahedra, and  an edgeedge with one Li(1)O4 trigonal pyramid. The corner-sharing octahedral tilt angles range from 50-53°. The Mo(1)-O(1) bond length is 2.11 Å. The Mo(1)-O(3) bond length is 2.08 Å. Both Mo(1)-O(2) bond lengths are 2.05 Å. Both Mo(1)-O(4) bond lengths are 2.11 Å. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted tetrahedral geometry to one Li(1) and three equivalent Mo(1) atoms. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Y(1) and two equivalent Mo(1) atoms. In the third O site, O(3) is bonded in a distorted T-shaped geometry to three equivalent Mo(1) atoms. In the fourth O site, O(4) is bonded in a distorted rectangular see-saw-like geometry to one Li(1), one Y(1), and two equivalent Mo(1) atoms.