Tm3Pr is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Tm sites. In the first Tm site, Tm(1) is bonded to four equivalent Tm(1), four equivalent Tm(2), and four equivalent Pr(1) atoms to form TmPr4Tm8 cuboctahedra that share corners with twelve equivalent Tm(1)Pr4Tm8 cuboctahedra, edges with eight equivalent Tm(1)Pr4Tm8 cuboctahedra, edges with eight equivalent Tm(2)Pr4Tm8 cuboctahedra, edges with eight equivalent Pr(1)Tm12 cuboctahedra, faces with four equivalent Tm(2)Pr4Tm8 cuboctahedra, faces with four equivalent Pr(1)Tm12 cuboctahedra, and faces with ten equivalent Tm(1)Pr4Tm8 cuboctahedra. In the second Tm site, Tm(2) is bonded to eight equivalent Tm(1) and four equivalent Pr(1) atoms to form TmPr4Tm8 cuboctahedra that share corners with four equivalent Tm(2)Pr4Tm8 cuboctahedra, corners with eight equivalent Pr(1)Tm12 cuboctahedra, edges with eight equivalent Tm(2)Pr4Tm8 cuboctahedra, edges with sixteen equivalent Tm(1)Pr4Tm8 cuboctahedra, faces with four equivalent Tm(2)Pr4Tm8 cuboctahedra, faces with six equivalent Pr(1)Tm12 cuboctahedra, and faces with eight equivalent Tm(1)Pr4Tm8 cuboctahedra. Pr(1) is bonded to four equivalent Tm(2) and eight equivalent Tm(1) atoms to form PrTm12 cuboctahedra that share corners with four equivalent Pr(1)Tm12 cuboctahedra, corners with eight equivalent Tm(2)Pr4Tm8 cuboctahedra, edges with eight equivalent Pr(1)Tm12 cuboctahedra, edges with sixteen equivalent Tm(1)Pr4Tm8 cuboctahedra, faces with four equivalent Pr(1)Tm12 cuboctahedra, faces with six equivalent Tm(2)Pr4Tm8 cuboctahedra, and faces with eight equivalent Tm(1)Pr4Tm8 cuboctahedra.
Tm3Pr is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Tm sites. In the first Tm site, Tm(1) is bonded to four equivalent Tm(1), four equivalent Tm(2), and four equivalent Pr(1) atoms to form TmPr4Tm8 cuboctahedra that share corners with twelve equivalent Tm(1)Pr4Tm8 cuboctahedra, edges with eight equivalent Tm(1)Pr4Tm8 cuboctahedra, edges with eight equivalent Tm(2)Pr4Tm8 cuboctahedra, edges with eight equivalent Pr(1)Tm12 cuboctahedra, faces with four equivalent Tm(2)Pr4Tm8 cuboctahedra, faces with four equivalent Pr(1)Tm12 cuboctahedra, and faces with ten equivalent Tm(1)Pr4Tm8 cuboctahedra. All Tm(1)-Tm(1) bond lengths are 3.57 Å. All Tm(1)-Tm(2) bond lengths are 3.54 Å. All Tm(1)-Pr(1) bond lengths are 3.54 Å. In the second Tm site, Tm(2) is bonded to eight equivalent Tm(1) and four equivalent Pr(1) atoms to form TmPr4Tm8 cuboctahedra that share corners with four equivalent Tm(2)Pr4Tm8 cuboctahedra, corners with eight equivalent Pr(1)Tm12 cuboctahedra, edges with eight equivalent Tm(2)Pr4Tm8 cuboctahedra, edges with sixteen equivalent Tm(1)Pr4Tm8 cuboctahedra, faces with four equivalent Tm(2)Pr4Tm8 cuboctahedra, faces with six equivalent Pr(1)Tm12 cuboctahedra, and faces with eight equivalent Tm(1)Pr4Tm8 cuboctahedra. All Tm(2)-Pr(1) bond lengths are 3.57 Å. Pr(1) is bonded to four equivalent Tm(2) and eight equivalent Tm(1) atoms to form PrTm12 cuboctahedra that share corners with four equivalent Pr(1)Tm12 cuboctahedra, corners with eight equivalent Tm(2)Pr4Tm8 cuboctahedra, edges with eight equivalent Pr(1)Tm12 cuboctahedra, edges with sixteen equivalent Tm(1)Pr4Tm8 cuboctahedra, faces with four equivalent Pr(1)Tm12 cuboctahedra, faces with six equivalent Tm(2)Pr4Tm8 cuboctahedra, and faces with eight equivalent Tm(1)Pr4Tm8 cuboctahedra.