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.
Thermionic work functions and desorption energies for oxygen on polycrystalline W, Mo and Re filaments, discussing oxygen pressure and filament temperature
ReO2 is beta Vanadium nitride-like structured and crystallizes in the tetragonal P4_2/mnm space group. The structure is three-dimensional. Re4+ is bonded to six equivalent O2- atoms to form a mixture of edge and corner-sharing ReO6 octahedra. The corner-sharing octahedral tilt angles are 42°. There are two shorter (1.97 Å) and four longer (2.04 Å) Re–O bond lengths. O2- is bonded in a 3-coordinate geometry to three equivalent Re4+ atoms.
ReO3 is alpha Rhenium trioxide structured and crystallizes in the trigonal R-3c space group. The structure is three-dimensional. Re6+ is bonded to six equivalent O2- atoms to form corner-sharing ReO6 octahedra. The corner-sharing octahedral tilt angles are 3°. All Re–O bond lengths are 1.90 Å. O2- is bonded in a linear geometry to two equivalent Re6+ atoms.
ReO3 is alpha Rhenium trioxide structured and crystallizes in the cubic Im-3 space group. The structure is three-dimensional. Re6+ is bonded to six equivalent O2- atoms to form corner-sharing ReO6 octahedra. The corner-sharing octahedral tilt angles are 6°. All Re–O bond lengths are 1.90 Å. O2- is bonded in a linear geometry to two equivalent Re6+ atoms.
Re3O8 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are two inequivalent Re+5.33+ sites. In the first Re+5.33+ site, Re+5.33+ is bonded to six O2- atoms to form corner-sharing ReO6 octahedra. The corner-sharing octahedra tilt angles range from 39–44°. There is four shorter (1.90 Å) and two longer (2.00 Å) Re–O bond length. In the second Re+5.33+ site, Re+5.33+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing ReO6 octahedra. The corner-sharing octahedra tilt angles range from 39–44°. There are a spread of Re–O bond distances ranging from 1.90–2.06 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted T-shaped geometry to three Re+5.33+ atoms. In the second O2- site, O2- is bonded in a bent 150 degrees geometry to two Re+5.33+ atoms. In the third O2- site, O2- is bonded in an L-shaped geometry to two equivalent Re+5.33+ atoms.
ReO3 is High-temperature superconductor-like structured and crystallizes in the tetragonal P4/mbm space group. The structure is three-dimensional. Re6+ is bonded to six O2- atoms to form corner-sharing ReO6 octahedra. The corner-sharing octahedra tilt angles range from 0–6°. All Re–O bond lengths are 1.90 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a linear geometry to two equivalent Re6+ atoms. In the second O2- site, O2- is bonded in a linear geometry to two equivalent Re6+ atoms. In the third O2- site, O2- is bonded in a linear geometry to two equivalent Re6+ atoms. In the fourth O2- site, O2- is bonded in a linear geometry to two equivalent Re6+ atoms.
ReO2 is beta Vanadium nitride-like structured and crystallizes in the orthorhombic Pbcn space group. The structure is three-dimensional. Re4+ is bonded to six equivalent O2- atoms to form a mixture of edge and corner-sharing ReO6 octahedra. The corner-sharing octahedra tilt angles range from 43–44°. There are two shorter (2.00 Å) and four longer (2.03 Å) Re–O bond lengths. O2- is bonded in a 3-coordinate geometry to three equivalent Re4+ atoms.
ReO3 is High-temperature superconductor-like structured and crystallizes in the trigonal R-3c space group. The structure is three-dimensional. Re6+ is bonded to six equivalent O2- atoms to form corner-sharing ReO6 octahedra. The corner-sharing octahedral tilt angles are 9°. All Re–O bond lengths are 1.90 Å. O2- is bonded in a linear geometry to two equivalent Re6+ atoms.
ReO3 is Upper Bainite structured and crystallizes in the hexagonal P6_322 space group. The structure is three-dimensional. Re6+ is bonded to six equivalent O2- atoms to form corner-sharing ReO6 octahedra. The corner-sharing octahedral tilt angles are 37°. All Re–O bond lengths are 1.91 Å. O2- is bonded in a bent 150 degrees geometry to two equivalent Re6+ atoms.
Re2O7 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are four inequivalent Re7+ sites. In the first Re7+ site, Re7+ is bonded to six O2- atoms to form ReO6 octahedra that share corners with six ReO6 octahedra and corners with five OO5 square pyramids. The corner-sharing octahedra tilt angles range from 25–52°. There are a spread of Re–O bond distances ranging from 1.82–2.03 Å. In the second Re7+ site, Re7+ is bonded to six O2- atoms to form ReO6 octahedra that share corners with six ReO6 octahedra and corners with five OO5 square pyramids. The corner-sharing octahedra tilt angles range from 25–52°. There are a spread of Re–O bond distances ranging from 1.83–2.03 Å. In the third Re7+ site, Re7+ is bonded to six O2- atoms to form ReO6 octahedra that share corners with six ReO6 octahedra and corners with five OO5 square pyramids. The corner-sharing octahedra tilt angles range from 25–52°. There are a spread of Re–O bond distances ranging from 1.83–2.02 Å. In the fourth Re7+ site, Re7+ is bonded to six O2- atoms to form ReO6 octahedra that share corners with six ReO6 octahedra and corners with five OO5 square pyramids. The corner-sharing octahedra tilt angles range from 25–52°. There are a spread of Re–O bond distances ranging from 1.83–2.03 Å. There are fourteen inequivalent O2- sites. In the first O2- site, O2- is bonded to five O2- atoms to form OO5 square pyramids that share corners with ten ReO6 octahedra. The corner-sharing octahedra tilt angles range from 64–75°. There are a spread of O–O bond distances ranging from 3.13–3.22 Å. In the second O2- site, O2- is bonded to five O2- atoms to form distorted OO5 square pyramids that share corners with ten ReO6 octahedra. The corner-sharing octahedra tilt angles range from 64–75°. There are a spread of O–O bond distances ranging from 3.15–3.23 Å. In the third O2- site, O2- is bonded in a bent 120 degrees geometry to two Re7+ and one O2- atom. In the fourth O2- site, O2- is bonded in a bent 120 degrees geometry to two Re7+ and one O2- atom. In the fifth O2- site, O2- is bonded in a bent 150 degrees geometry to two Re7+ and one O2- atom. In the sixth O2- site, O2- is bonded in a bent 150 degrees geometry to two Re7+ and one O2- atom. In the seventh O2- site, O2- is bonded in a bent 150 degrees geometry to two Re7+ and one O2- atom. In the eighth O2- site, O2- is bonded in a bent 150 degrees geometry to two Re7+ and one O2- atom. In the ninth O2- site, O2- is bonded in a bent 150 degrees geometry to two Re7+ atoms. In the tenth O2- site, O2- is bonded in a bent 150 degrees geometry to two Re7+ and one O2- atom. In the eleventh O2- site, O2- is bonded in a bent 150 degrees geometry to two Re7+ and one O2- atom. In the twelfth O2- site, O2- is bonded in a bent 150 degrees geometry to two Re7+ atoms. In the thirteenth O2- site, O2- is bonded in a bent 150 degrees geometry to two Re7+ and one O2- atom. In the fourteenth O2- site, O2- is bonded in a bent 150 degrees geometry to two Re7+ and one O2- atom.