DOE OSTI2020
PuNpB4 is hexagonal omega structure-derived structured and crystallizes in the hexagonal P6/mmm space group. The structure is three-dimensional. Pu3+ is bonded to twelve equivalent B+1.50- atoms to form PuB12 cuboctahedra that share edges with twelve equivalent NpB12 cuboctahedra, faces with two equivalent NpB12 cuboctahedra, and faces with six equivalent PuB12 cuboctahedra. All Pu–B bond lengths are 2.69 Å. Np3+ is bonded to twelve equivalent B+1.50- atoms to form NpB12 cuboctahedra that share edges with twelve equivalent PuB12 cuboctahedra, faces with two equivalent PuB12 cuboctahedra, and faces with six equivalent NpB12 cuboctahedra. All Np–B bond lengths are 2.68 Å. B+1.50- is bonded in a 3-coordinate geometry to three equivalent Pu3+, three equivalent Np3+, and three equivalent B+1.50- atoms. All B–B bond lengths are 1.79 Å.