U2Ga2O5 crystallizes in the tetragonal P4/mmm space group. There are two inequivalent U sites. In the first U site, U(1) is bonded in a body-centered cubic geometry to eight equivalent O(1) atoms. In the second U site, U(2) is bonded to four equivalent O(2) and eight equivalent O(1) atoms to form UO12 cuboctahedra that share corners with four equivalent U(2)O12 cuboctahedra, faces with four equivalent U(2)O12 cuboctahedra, and faces with eight equivalent Ga(1)O5 square pyramids. Ga(1) is bonded to one O(2) and four equivalent O(1) atoms to form GaO5 square pyramids that share corners with five equivalent Ga(1)O5 square pyramids and faces with four equivalent U(2)O12 cuboctahedra. There are two inequivalent O sites. In the first O site, O(1) is bonded to two equivalent U(1), two equivalent U(2), and two equivalent Ga(1) atoms to form a mixture of distorted face, corner, and edge-sharing OU4Ga2 octahedra. The corner-sharing octahedral tilt angles range from 0-67°. In the second O site, O(2) is bonded in a linear geometry to four equivalent U(2) and two equivalent Ga(1) atoms.
U2Ga2O5 crystallizes in the tetragonal P4/mmm space group. There are two inequivalent U sites. In the first U site, U(1) is bonded in a body-centered cubic geometry to eight equivalent O(1) atoms. All U(1)-O(1) bond lengths are 2.59 Å. In the second U site, U(2) is bonded to four equivalent O(2) and eight equivalent O(1) atoms to form UO12 cuboctahedra that share corners with four equivalent U(2)O12 cuboctahedra, faces with four equivalent U(2)O12 cuboctahedra, and faces with eight equivalent Ga(1)O5 square pyramids. All U(2)-O(2) bond lengths are 2.85 Å. All U(2)-O(1) bond lengths are 2.69 Å. Ga(1) is bonded to one O(2) and four equivalent O(1) atoms to form GaO5 square pyramids that share corners with five equivalent Ga(1)O5 square pyramids and faces with four equivalent U(2)O12 cuboctahedra. The Ga(1)-O(2) bond length is 1.98 Å. All Ga(1)-O(1) bond lengths are 2.02 Å. There are two inequivalent O sites. In the first O site, O(1) is bonded to two equivalent U(1), two equivalent U(2), and two equivalent Ga(1) atoms to form a mixture of distorted face, corner, and edge-sharing OU4Ga2 octahedra. The corner-sharing octahedral tilt angles range from 0-67°. In the second O site, O(2) is bonded in a linear geometry to four equivalent U(2) and two equivalent Ga(1) atoms.