Er2Mn3Ga crystallizes in the hexagonal P6_3/mmc space group. Er(1) is bonded in a 16-coordinate geometry to four equivalent Er(1), nine equivalent Mn(1), and three equivalent Ga(1) atoms. Mn(1) is bonded to six equivalent Er(1), four equivalent Mn(1), and two equivalent Ga(1) atoms to form distorted MnEr6Mn4Ga2 cuboctahedra that share corners with four equivalent Ga(1)Er6Mn6 cuboctahedra, corners with fourteen equivalent Mn(1)Er6Mn4Ga2 cuboctahedra, edges with six equivalent Mn(1)Er6Mn4Ga2 cuboctahedra, faces with six equivalent Ga(1)Er6Mn6 cuboctahedra, and faces with twelve equivalent Mn(1)Er6Mn4Ga2 cuboctahedra. Ga(1) is bonded to six equivalent Er(1) and six equivalent Mn(1) atoms to form GaEr6Mn6 cuboctahedra that share corners with twelve equivalent Mn(1)Er6Mn4Ga2 cuboctahedra, edges with six equivalent Ga(1)Er6Mn6 cuboctahedra, faces with two equivalent Ga(1)Er6Mn6 cuboctahedra, and faces with eighteen equivalent Mn(1)Er6Mn4Ga2 cuboctahedra.
Er2Mn3Ga crystallizes in the hexagonal P6_3/mmc space group. Er(1) is bonded in a 16-coordinate geometry to four equivalent Er(1), nine equivalent Mn(1), and three equivalent Ga(1) atoms. There is one shorter (3.13 Å) and three longer (3.30 Å) Er(1)-Er(1) bond lengths. There are three shorter (3.05 Å) and six longer (3.12 Å) Er(1)-Mn(1) bond lengths. All Er(1)-Ga(1) bond lengths are 3.16 Å. Mn(1) is bonded to six equivalent Er(1), four equivalent Mn(1), and two equivalent Ga(1) atoms to form distorted MnEr6Mn4Ga2 cuboctahedra that share corners with four equivalent Ga(1)Er6Mn6 cuboctahedra, corners with fourteen equivalent Mn(1)Er6Mn4Ga2 cuboctahedra, edges with six equivalent Mn(1)Er6Mn4Ga2 cuboctahedra, faces with six equivalent Ga(1)Er6Mn6 cuboctahedra, and faces with twelve equivalent Mn(1)Er6Mn4Ga2 cuboctahedra. There are two shorter (2.57 Å) and two longer (2.82 Å) Mn(1)-Mn(1) bond lengths. Both Mn(1)-Ga(1) bond lengths are 2.67 Å. Ga(1) is bonded to six equivalent Er(1) and six equivalent Mn(1) atoms to form GaEr6Mn6 cuboctahedra that share corners with twelve equivalent Mn(1)Er6Mn4Ga2 cuboctahedra, edges with six equivalent Ga(1)Er6Mn6 cuboctahedra, faces with two equivalent Ga(1)Er6Mn6 cuboctahedra, and faces with eighteen equivalent Mn(1)Er6Mn4Ga2 cuboctahedra.