SEARCH · Engineering Papers
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.
ZrB12 crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. Zr is bonded in a 1-coordinate geometry to twenty-four equivalent B atoms. All Zr–B bond lengths are 2.75 Å. B is bonded in a 7-coordinate geometry to two equivalent Zr and five equivalent B atoms. There is one shorter (1.69 Å) and four longer (1.78 Å) B–B bond length.
ZrB2(HfB2) is hexagonal omega structure-derived structured and crystallizes in the orthorhombic Pmmm space group. The structure is three-dimensional. Hf4+ is bonded to twelve B+1.50- atoms to form HfB12 cuboctahedra that share edges with four equivalent HfB12 cuboctahedra, edges with eight equivalent ZrB12 cuboctahedra, faces with four equivalent HfB12 cuboctahedra, and faces with four equivalent ZrB12 cuboctahedra. All Hf–B bond lengths are 2.53 Å. Zr2+ is bonded to twelve B+1.50- atoms to form ZrB12 cuboctahedra that share edges with four equivalent ZrB12 cuboctahedra, edges with eight equivalent HfB12 cuboctahedra, faces with four equivalent HfB12 cuboctahedra, and faces with four equivalent ZrB12 cuboctahedra. All Zr–B bond lengths are 2.54 Å. There are two inequivalent B+1.50- sites. In the first B+1.50- site, B+1.50- is bonded in a 9-coordinate geometry to two equivalent Hf4+, four equivalent Zr2+, and three B+1.50- atoms. There is two shorter (1.83 Å) and one longer (1.84 Å) B–B bond length. In the second B+1.50- site, B+1.50- is bonded in a 9-coordinate geometry to four equivalent Hf4+, two equivalent Zr2+, and three B+1.50- atoms. The B–B bond length is 1.81 Å.
ZrNbB4 is hexagonal omega structure-derived structured and crystallizes in the hexagonal P6/mmm space group. The structure is three-dimensional. Zr4+ is bonded to twelve equivalent B+1.50- atoms to form ZrB12 cuboctahedra that share edges with twelve equivalent NbB12 cuboctahedra, faces with two equivalent NbB12 cuboctahedra, and faces with six equivalent ZrB12 cuboctahedra. All Zr–B bond lengths are 2.54 Å. Nb2+ is bonded to twelve equivalent B+1.50- atoms to form NbB12 cuboctahedra that share edges with twelve equivalent ZrB12 cuboctahedra, faces with two equivalent ZrB12 cuboctahedra, and faces with six equivalent NbB12 cuboctahedra. All Nb–B bond lengths are 2.47 Å. B+1.50- is bonded in a 9-coordinate geometry to three equivalent Zr4+, three equivalent Nb2+, and three equivalent B+1.50- atoms. All B–B bond lengths are 1.82 Å.
ZrTiB4 is hexagonal omega structure-derived structured and crystallizes in the hexagonal P6/mmm space group. The structure is three-dimensional. Zr2+ is bonded to twelve equivalent B+1.50- atoms to form ZrB12 cuboctahedra that share edges with twelve equivalent TiB12 cuboctahedra, faces with two equivalent TiB12 cuboctahedra, and faces with six equivalent ZrB12 cuboctahedra. All Zr–B bond lengths are 2.55 Å. Ti4+ is bonded to twelve equivalent B+1.50- atoms to form TiB12 cuboctahedra that share edges with twelve equivalent ZrB12 cuboctahedra, faces with two equivalent ZrB12 cuboctahedra, and faces with six equivalent TiB12 cuboctahedra. All Ti–B bond lengths are 2.39 Å. B+1.50- is bonded in a 9-coordinate geometry to three equivalent Zr2+, three equivalent Ti4+, and three equivalent B+1.50- atoms. All B–B bond lengths are 1.79 Å.
ZrTaB4 is hexagonal omega structure-derived structured and crystallizes in the hexagonal P6/mmm space group. The structure is three-dimensional. Zr2+ is bonded to twelve equivalent B+1.50- atoms to form ZrB12 cuboctahedra that share edges with twelve equivalent TaB12 cuboctahedra, faces with two equivalent TaB12 cuboctahedra, and faces with six equivalent ZrB12 cuboctahedra. All Zr–B bond lengths are 2.54 Å. Ta4+ is bonded to twelve equivalent B+1.50- atoms to form TaB12 cuboctahedra that share edges with twelve equivalent ZrB12 cuboctahedra, faces with two equivalent ZrB12 cuboctahedra, and faces with six equivalent TaB12 cuboctahedra. All Ta–B bond lengths are 2.45 Å. B+1.50- is bonded in a 9-coordinate geometry to three equivalent Zr2+, three equivalent Ta4+, and three equivalent B+1.50- atoms. All B–B bond lengths are 1.81 Å.
ZrMoB4 is hexagonal omega structure-derived structured and crystallizes in the hexagonal P6/mmm space group. The structure is three-dimensional. Zr4+ is bonded to twelve equivalent B+1.50- atoms to form ZrB12 cuboctahedra that share edges with twelve equivalent MoB12 cuboctahedra, faces with two equivalent MoB12 cuboctahedra, and faces with six equivalent ZrB12 cuboctahedra. All Zr–B bond lengths are 2.52 Å. Mo2+ is bonded to twelve equivalent B+1.50- atoms to form MoB12 cuboctahedra that share edges with twelve equivalent ZrB12 cuboctahedra, faces with two equivalent ZrB12 cuboctahedra, and faces with six equivalent MoB12 cuboctahedra. All Mo–B bond lengths are 2.43 Å. B+1.50- is bonded in a 9-coordinate geometry to three equivalent Zr4+, three equivalent Mo2+, and three equivalent B+1.50- atoms. All B–B bond lengths are 1.81 Å.
ZrB2 is hexagonal omega structure structured and crystallizes in the hexagonal P6/mmm space group. The structure is three-dimensional. Zr is bonded to twelve equivalent B atoms to form a mixture of edge and face-sharing ZrB12 cuboctahedra. All Zr–B bond lengths are 2.55 Å. B is bonded in a 9-coordinate geometry to six equivalent Zr and three equivalent B atoms. All B–B bond lengths are 1.84 Å.