SEARCH · Search NASA
Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
PaSi3 is Uranium Silicide structured and crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. Pa4+ is bonded to twelve equivalent Si+1.33- atoms to form a mixture of face and corner-sharing PaSi12 cuboctahedra. All Pa–Si bond lengths are 2.91 Å. Si+1.33- is bonded in a distorted square co-planar geometry to four equivalent Pa4+ atoms.
Pa3Si is Uranium Silicide structured and crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. Pa is bonded to eight equivalent Pa and four equivalent Si atoms to form distorted PaPa8Si4 cuboctahedra that share corners with twelve equivalent PaPa8Si4 cuboctahedra, edges with eight equivalent SiPa12 cuboctahedra, edges with sixteen equivalent PaPa8Si4 cuboctahedra, faces with four equivalent SiPa12 cuboctahedra, and faces with fourteen equivalent PaPa8Si4 cuboctahedra. All Pa–Pa bond lengths are 3.14 Å. All Pa–Si bond lengths are 3.14 Å. Si is bonded to twelve equivalent Pa atoms to form SiPa12 cuboctahedra that share corners with twelve equivalent SiPa12 cuboctahedra, edges with twenty-four equivalent PaPa8Si4 cuboctahedra, faces with six equivalent SiPa12 cuboctahedra, and faces with twelve equivalent PaPa8Si4 cuboctahedra.
PaSi3 crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Pa4+ is bonded to twelve equivalent Si+1.33- atoms to form a mixture of corner and face-sharing PaSi12 cuboctahedra. There are six shorter (2.96 Å) and six longer (2.98 Å) Pa–Si bond lengths. Si+1.33- is bonded in a 10-coordinate geometry to four equivalent Pa4+ and six equivalent Si+1.33- atoms. There are two shorter (2.55 Å) and four longer (2.69 Å) Si–Si bond lengths.