Materials Data on TiNb3(AlC)2 by Materials Project
TiNb3(AlC)2 is H-Phase-derived structured and crystallizes in the trigonal P3m1 space group. The structure is three-dimensional. Ti is bonded in a 3-coordinate geometry to three equivalent Al and three equivalent C atoms. All Ti–Al bond lengths are 2.89 Å. All Ti–C bond lengths are 2.12 Å. There are three inequivalent Nb sites. In the first Nb site, Nb is bonded in a 3-coordinate geometry to three equivalent Al and three equivalent C atoms. All Nb–Al bond lengths are 2.88 Å. All Nb–C bond lengths are 2.21 Å. In the second Nb site, Nb is bonded in a 3-coordinate geometry to three equivalent Al and three equivalent C atoms. All Nb–Al bond lengths are 2.86 Å. All Nb–C bond lengths are 2.19 Å. In the third Nb site, Nb is bonded in a 3-coordinate geometry to three equivalent Al and three equivalent C atoms. All Nb–Al bond lengths are 2.88 Å. All Nb–C bond lengths are 2.19 Å. There are two inequivalent Al sites. In the first Al site, Al is bonded to six Nb atoms to form distorted AlNb6 cuboctahedra that share corners with six CTi3Nb3 octahedra, edges with six equivalent AlNb6 cuboctahedra, and edges with six CTi3Nb3 octahedra. The corner-sharing octahedral tilt angles are 16°. In the second Al site, Al is bonded in a 12-coordinate geometry to three equivalent Ti and three equivalent Nb atoms. There are two inequivalent C sites. In the first C site, C is bonded to three equivalent Ti and three equivalent Nb atoms to form CTi3Nb3 octahedra that share corners with three equivalent AlNb6 cuboctahedra, edges with three equivalent AlNb6 cuboctahedra, and edges with six equivalent CTi3Nb3 octahedra. In the second C site, C is bonded to six Nb atoms to form CNb6 octahedra that share corners with three equivalent AlNb6 cuboctahedra, edges with three equivalent AlNb6 cuboctahedra, and edges with six equivalent CNb6 octahedra.