NpSi2 is hexagonal omega structure-like structured and crystallizes in the tetragonal I4_1/amd space group. Np(1) is bonded to twelve equivalent Si(1) atoms to form a mixture of face and edge-sharing NpSi12 cuboctahedra. Si(1) is bonded in a 9-coordinate geometry to six equivalent Np(1) and three equivalent Si(1) atoms.
NpSi2 is hexagonal omega structure-like structured and crystallizes in the tetragonal I4_1/amd space group. Np(1) is bonded to twelve equivalent Si(1) atoms to form a mixture of face and edge-sharing NpSi12 cuboctahedra. There are eight shorter (3.03 Å) and four longer (3.10 Å) Np(1)-Si(1) bond lengths. Si(1) is bonded in a 9-coordinate geometry to six equivalent Np(1) and three equivalent Si(1) atoms. There are two shorter (2.32 Å) and one longer (2.34 Å) Si(1)-Si(1) bond length.