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.
Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations
CrAl4S8 crystallizes in the cubic F-43m space group. The structure is three-dimensional. Cr4+ is bonded to four equivalent S2- atoms to form CrS4 tetrahedra that share corners with twelve equivalent AlS6 octahedra. The corner-sharing octahedral tilt angles are 60°. All Cr–S bond lengths are 2.21 Å. Al3+ is bonded to six S2- atoms to form AlS6 octahedra that share corners with three equivalent CrS4 tetrahedra and edges with six equivalent AlS6 octahedra. There are three shorter (2.32 Å) and three longer (2.59 Å) Al–S bond lengths. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded to one Cr4+ and three equivalent Al3+ atoms to form a mixture of distorted corner and edge-sharing SAl3Cr tetrahedra. In the second S2- site, S2- is bonded in a 3-coordinate geometry to three equivalent Al3+ atoms.