K3Pr is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. K(1) is bonded to eight equivalent K(1) and four equivalent Pr(1) atoms to form distorted KK8Pr4 cuboctahedra that share corners with four equivalent Pr(1)K12 cuboctahedra, corners with fourteen equivalent K(1)K8Pr4 cuboctahedra, edges with six equivalent Pr(1)K12 cuboctahedra, edges with twelve equivalent K(1)K8Pr4 cuboctahedra, faces with four equivalent Pr(1)K12 cuboctahedra, and faces with sixteen equivalent K(1)K8Pr4 cuboctahedra. Pr(1) is bonded to twelve equivalent K(1) atoms to form PrK12 cuboctahedra that share corners with six equivalent Pr(1)K12 cuboctahedra, corners with twelve equivalent K(1)K8Pr4 cuboctahedra, edges with eighteen equivalent K(1)K8Pr4 cuboctahedra, faces with eight equivalent Pr(1)K12 cuboctahedra, and faces with twelve equivalent K(1)K8Pr4 cuboctahedra.
K3Pr is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. K(1) is bonded to eight equivalent K(1) and four equivalent Pr(1) atoms to form distorted KK8Pr4 cuboctahedra that share corners with four equivalent Pr(1)K12 cuboctahedra, corners with fourteen equivalent K(1)K8Pr4 cuboctahedra, edges with six equivalent Pr(1)K12 cuboctahedra, edges with twelve equivalent K(1)K8Pr4 cuboctahedra, faces with four equivalent Pr(1)K12 cuboctahedra, and faces with sixteen equivalent K(1)K8Pr4 cuboctahedra. There are a spread of K(1)-K(1) bond distances ranging from 4.23-4.45 Å. All K(1)-Pr(1) bond lengths are 4.34 Å. Pr(1) is bonded to twelve equivalent K(1) atoms to form PrK12 cuboctahedra that share corners with six equivalent Pr(1)K12 cuboctahedra, corners with twelve equivalent K(1)K8Pr4 cuboctahedra, edges with eighteen equivalent K(1)K8Pr4 cuboctahedra, faces with eight equivalent Pr(1)K12 cuboctahedra, and faces with twelve equivalent K(1)K8Pr4 cuboctahedra.