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.
SiC2N4 crystallizes in the cubic Pn-3m space group. The structure is three-dimensional. Si4+ is bonded in a tetrahedral geometry to four equivalent N3- atoms. All Si–N bond lengths are 1.69 Å. C4+ is bonded in a linear geometry to two equivalent N3- atoms. Both C–N bond lengths are 1.21 Å. N3- is bonded in a linear geometry to one Si4+ and one C4+ atom.
Si2CN4 crystallizes in the orthorhombic Aea2 space group. The structure is three-dimensional. Si4+ is bonded to four N3- atoms to form corner-sharing SiN4 tetrahedra. There is one shorter (1.70 Å) and three longer (1.74 Å) Si–N bond length. C4+ is bonded in a linear geometry to two equivalent N3- atoms. Both C–N bond lengths are 1.21 Å. There are two inequivalent N3- sites. In the first N3- site, N3- is bonded in a linear geometry to one Si4+ and one C4+ atom. In the second N3- site, N3- is bonded in a trigonal planar geometry to three equivalent Si4+ atoms.
SiCN is half-Heusler structured and crystallizes in the cubic F-43m space group. The structure is three-dimensional. Si4+ is bonded in a body-centered cubic geometry to four equivalent C2- and four equivalent N2- atoms. All Si–C bond lengths are 2.06 Å. All Si–N bond lengths are 2.06 Å. C2- is bonded to four equivalent Si4+ atoms to form CSi4 tetrahedra that share corners with four equivalent NSi4 tetrahedra, corners with twelve equivalent CSi4 tetrahedra, and edges with six equivalent NSi4 tetrahedra. N2- is bonded to four equivalent Si4+ atoms to form NSi4 tetrahedra that share corners with four equivalent CSi4 tetrahedra, corners with twelve equivalent NSi4 tetrahedra, and edges with six equivalent CSi4 tetrahedra.