V2Cr2GaSe8 crystallizes in the orthorhombic Imm2 space group. V(1) is bonded to one Se(1), one Se(3), two equivalent Se(2), and two equivalent Se(4) atoms to form VSe6 octahedra that share corners with three equivalent Ga(1)Se4 tetrahedra, edges with two equivalent V(1)Se6 octahedra, and edges with four equivalent Cr(1)Se6 octahedra. Cr(1) is bonded to one Se(2), one Se(4), two equivalent Se(1), and two equivalent Se(3) atoms to form CrSe6 octahedra that share corners with three equivalent Ga(1)Se4 tetrahedra, edges with two equivalent Cr(1)Se6 octahedra, and edges with four equivalent V(1)Se6 octahedra. Ga(1) is bonded to two equivalent Se(3) and two equivalent Se(4) atoms to form GaSe4 tetrahedra that share corners with six equivalent V(1)Se6 octahedra and corners with six equivalent Cr(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 62-63°. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded in a distorted T-shaped geometry to one V(1) and two equivalent Cr(1) atoms. In the second Se site, Se(2) is bonded in a distorted T-shaped geometry to two equivalent V(1) and one Cr(1) atom. In the third Se site, Se(3) is bonded to one V(1), two equivalent Cr(1), and one Ga(1) atom to form SeVCr2Ga tetrahedra that share  a cornercorner with one Se(3)VCr2Ga tetrahedra, corners with two equivalent Se(4)V2CrGa tetrahedra,  an edgeedge with one Se(3)VCr2Ga tetrahedra, and edges with two equivalent Se(4)V2CrGa tetrahedra. In the fourth Se site, Se(4) is bonded to two equivalent V(1), one Cr(1), and one Ga(1) atom to form SeV2CrGa tetrahedra that share  a cornercorner with one Se(4)V2CrGa tetrahedra, corners with two equivalent Se(3)VCr2Ga tetrahedra,  an edgeedge with one Se(4)V2CrGa tetrahedra, and edges with two equivalent Se(3)VCr2Ga tetrahedra.
V2Cr2GaSe8 crystallizes in the orthorhombic Imm2 space group. V(1) is bonded to one Se(1), one Se(3), two equivalent Se(2), and two equivalent Se(4) atoms to form VSe6 octahedra that share corners with three equivalent Ga(1)Se4 tetrahedra, edges with two equivalent V(1)Se6 octahedra, and edges with four equivalent Cr(1)Se6 octahedra. The V(1)-Se(1) bond length is 2.44 Å. The V(1)-Se(3) bond length is 2.67 Å. Both V(1)-Se(2) bond lengths are 2.45 Å. Both V(1)-Se(4) bond lengths are 2.67 Å. Cr(1) is bonded to one Se(2), one Se(4), two equivalent Se(1), and two equivalent Se(3) atoms to form CrSe6 octahedra that share corners with three equivalent Ga(1)Se4 tetrahedra, edges with two equivalent Cr(1)Se6 octahedra, and edges with four equivalent V(1)Se6 octahedra. The Cr(1)-Se(2) bond length is 2.51 Å. The Cr(1)-Se(4) bond length is 2.58 Å. Both Cr(1)-Se(1) bond lengths are 2.48 Å. Both Cr(1)-Se(3) bond lengths are 2.61 Å. Ga(1) is bonded to two equivalent Se(3) and two equivalent Se(4) atoms to form GaSe4 tetrahedra that share corners with six equivalent V(1)Se6 octahedra and corners with six equivalent Cr(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 62-63°. Both Ga(1)-Se(3) bond lengths are 2.45 Å. Both Ga(1)-Se(4) bond lengths are 2.47 Å. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded in a distorted T-shaped geometry to one V(1) and two equivalent Cr(1) atoms. In the second Se site, Se(2) is bonded in a distorted T-shaped geometry to two equivalent V(1) and one Cr(1) atom. In the third Se site, Se(3) is bonded to one V(1), two equivalent Cr(1), and one Ga(1) atom to form SeVCr2Ga tetrahedra that share  a cornercorner with one Se(3)VCr2Ga tetrahedra, corners with two equivalent Se(4)V2CrGa tetrahedra,  an edgeedge with one Se(3)VCr2Ga tetrahedra, and edges with two equivalent Se(4)V2CrGa tetrahedra. In the fourth Se site, Se(4) is bonded to two equivalent V(1), one Cr(1), and one Ga(1) atom to form SeV2CrGa tetrahedra that share  a cornercorner with one Se(4)V2CrGa tetrahedra, corners with two equivalent Se(3)VCr2Ga tetrahedra,  an edgeedge with one Se(4)V2CrGa tetrahedra, and edges with two equivalent Se(3)VCr2Ga tetrahedra.