Ta2V4Al3C3 is H-Phase-derived structured and crystallizes in the trigonal P3m1 space group. There are four inequivalent Ta sites. In the first Ta site, Ta(1) is bonded in a 3-coordinate geometry to three equivalent Al(4) and three equivalent C(1) atoms. In the second Ta site, Ta(2) is bonded in a 3-coordinate geometry to three equivalent Al(5) and three equivalent C(2) atoms. In the third Ta site, Ta(3) is bonded in a 3-coordinate geometry to three equivalent Al(6) and three equivalent C(3) atoms. In the fourth Ta site, Ta(4) is bonded in a 3-coordinate geometry to three equivalent Al(1) and three equivalent C(1) atoms. There are eight inequivalent V sites. In the first V site, V(1) is bonded in a 3-coordinate geometry to three equivalent Al(2) and three equivalent C(2) atoms. In the second V site, V(2) is bonded in a 3-coordinate geometry to three equivalent Al(3) and three equivalent C(3) atoms. In the third V site, V(3) is bonded in a 3-coordinate geometry to three equivalent Al(1) and three equivalent C(4) atoms. In the fourth V site, V(4) is bonded in a 3-coordinate geometry to three equivalent Al(2) and three equivalent C(5) atoms. In the fifth V site, V(5) is bonded in a 3-coordinate geometry to three equivalent Al(3) and three equivalent C(6) atoms. In the sixth V site, V(6) is bonded in a 3-coordinate geometry to three equivalent Al(4) and three equivalent C(5) atoms. In the seventh V site, V(7) is bonded in a 3-coordinate geometry to three equivalent Al(5) and three equivalent C(6) atoms. In the eighth V site, V(8) is bonded in a 3-coordinate geometry to three equivalent Al(6) and three equivalent C(4) atoms. There are six inequivalent Al sites. In the first Al site, Al(1) is bonded to three equivalent Ta(4), three equivalent V(3), and six equivalent Al(1) atoms to form distorted AlTa3Al6V3 cuboctahedra that share corners with six equivalent Al(1)Ta3Al6V3 cuboctahedra, corners with three equivalent C(1)Ta6 octahedra, corners with three equivalent C(4)V6 octahedra, edges with six equivalent Al(1)Ta3Al6V3 cuboctahedra, edges with three equivalent C(1)Ta6 octahedra, edges with three equivalent C(4)V6 octahedra, and faces with six equivalent Al(1)Ta3Al6V3 cuboctahedra. The corner-sharing octahedral tilt angles range from 16-19°. In the second Al site, Al(2) is bonded to three equivalent V(1), three equivalent V(4), and six equivalent Al(2) atoms to form AlAl6V6 cuboctahedra that share corners with six equivalent Al(2)Al6V6 cuboctahedra, corners with three equivalent C(2)Ta3V3 octahedra, corners with three equivalent C(5)V6 octahedra, edges with six equivalent Al(2)Al6V6 cuboctahedra, edges with three equivalent C(2)Ta3V3 octahedra, edges with three equivalent C(5)V6 octahedra, and faces with six equivalent Al(2)Al6V6 cuboctahedra. The corner-sharing octahedral tilt angles range from 19-20°. In the third Al site, Al(3) is bonded to three equivalent V(2), three equivalent V(5), and six equivalent Al(3) atoms to form AlAl6V6 cuboctahedra that share corners with six equivalent Al(3)Al6V6 cuboctahedra, corners with three equivalent C(3)Ta3V3 octahedra, corners with three equivalent C(6)V6 octahedra, edges with six equivalent Al(3)Al6V6 cuboctahedra, edges with three equivalent C(3)Ta3V3 octahedra, edges with three equivalent C(6)V6 octahedra, and faces with six equivalent Al(3)Al6V6 cuboctahedra. The corner-sharing octahedral tilt angles range from 19-20°. In the fourth Al site, Al(4) is bonded to three equivalent Ta(1), three equivalent V(6), and six equivalent Al(4) atoms to form distorted AlTa3Al6V3 cuboctahedra that share corners with six equivalent Al(4)Ta3Al6V3 cuboctahedra, corners with three equivalent C(1)Ta6 octahedra, corners with three equivalent C(5)V6 octahedra, edges with six equivalent Al(4)Ta3Al6V3 cuboctahedra, edges with three equivalent C(1)Ta6 octahedra, edges with three equivalent C(5)V6 octahedra, and faces with six equivalent Al(4)Ta3Al6V3 cuboctahedra. The corner-sharing octahedral tilt angles range from 16-18°. In the fifth Al site, Al(5) is bonded to three equivalent Ta(2), three equivalent V(7), and six equivalent Al(5) atoms to form AlTa3Al6V3 cuboctahedra that share corners with six equivalent Al(5)Ta3Al6V3 cuboctahedra, corners with three equivalent C(2)Ta3V3 octahedra, corners with three equivalent C(6)V6 octahedra, edges with six equivalent Al(5)Ta3Al6V3 cuboctahedra, edges with three equivalent C(2)Ta3V3 octahedra, edges with three equivalent C(6)V6 octahedra, and faces with six equivalent Al(5)Ta3Al6V3 cuboctahedra. The corner-sharing octahedral tilt angles range from 16-19°. In the sixth Al site, Al(6) is bonded to three equivalent Ta(3), three equivalent V(8), and six equivalent Al(6) atoms to form distorted AlTa3Al6V3 cuboctahedra that share corners with six equivalent Al(6)Ta3Al6V3 cuboctahedra, corners with three equivalent C(3)Ta3V3 octahedra, corners with three equivalent C(4)V6 octahedra, edges with six equivalent Al(6)Ta3Al6V3 cuboctahedra, edges with three equivalent C(3)Ta3V3 octahedra, edges with three equivalent C(4)V6 octahedra, and faces with six equivalent Al(6)Ta3Al6V3 cuboctahedra. The corner-sharing octahedral tilt angles range from 16-19°. There are six inequivalent C sites. In the first C site, C(1) is bonded to three equivalent Ta(1) and three equivalent Ta(4) atoms to form CTa6 octahedra that share corners with three equivalent Al(1)Ta3Al6V3 cuboctahedra, corners with three equivalent Al(4)Ta3Al6V3 cuboctahedra, edges with three equivalent Al(1)Ta3Al6V3 cuboctahedra, edges with three equivalent Al(4)Ta3Al6V3 cuboctahedra, and edges with six equivalent C(1)Ta6 octahedra. In the second C site, C(2) is bonded to three equivalent Ta(2) and three equivalent V(1) atoms to form CTa3V3 octahedra that share corners with three equivalent Al(2)Al6V6 cuboctahedra, corners with three equivalent Al(5)Ta3Al6V3 cuboctahedra, edges with three equivalent Al(2)Al6V6 cuboctahedra, edges with three equivalent Al(5)Ta3Al6V3 cuboctahedra, and edges with six equivalent C(2)Ta3V3 octahedra. In the third C site, C(3) is bonded to three equivalent Ta(3) and three equivalent V(2) atoms to form CTa3V3 octahedra that share corners with three equivalent Al(3)Al6V6 cuboctahedra, corners with three equivalent Al(6)Ta3Al6V3 cuboctahedra, edges with three equivalent Al(3)Al6V6 cuboctahedra, edges with three equivalent Al(6)Ta3Al6V3 cuboctahedra, and edges with six equivalent C(3)Ta3V3 octahedra. In the fourth C site, C(4) is bonded to three equivalent V(3) and three equivalent V(8) atoms to form CV6 octahedra that share corners with three equivalent Al(1)Ta3Al6V3 cuboctahedra, corners with three equivalent Al(6)Ta3Al6V3 cuboctahedra, edges with three equivalent Al(1)Ta3Al6V3 cuboctahedra, edges with three equivalent Al(6)Ta3Al6V3 cuboctahedra, and edges with six equivalent C(4)V6 octahedra. In the fifth C site, C(5) is bonded to three equivalent V(4) and three equivalent V(6) atoms to form CV6 octahedra that share corners with three equivalent Al(2)Al6V6 cuboctahedra, corners with three equivalent Al(4)Ta3Al6V3 cuboctahedra, edges with three equivalent Al(2)Al6V6 cuboctahedra, edges with three equivalent Al(4)Ta3Al6V3 cuboctahedra, and edges with six equivalent C(5)V6 octahedra. In the sixth C site, C(6) is bonded to three equivalent V(5) and three equivalent V(7) atoms to form CV6 octahedra that share corners with three equivalent Al(3)Al6V6 cuboctahedra, corners with three equivalent Al(5)Ta3Al6V3 cuboctahedra, edges with three equivalent Al(3)Al6V6 cuboctahedra, edges with three equivalent Al(5)Ta3Al6V3 cuboctahedra, and edges with six equivalent C(6)V6 octahedra.
Ta2V4Al3C3 is H-Phase-derived structured and crystallizes in the trigonal P3m1 space group. There are four inequivalent Ta sites. In the first Ta site, Ta(1) is bonded in a 3-coordinate geometry to three equivalent Al(4) and three equivalent C(1) atoms. All Ta(1)-Al(4) bond lengths are 2.84 Å. All Ta(1)-C(1) bond lengths are 2.16 Å. In the second Ta site, Ta(2) is bonded in a 3-coordinate geometry to three equivalent Al(5) and three equivalent C(2) atoms. All Ta(2)-Al(5) bond lengths are 2.89 Å. All Ta(2)-C(2) bond lengths are 2.18 Å. In the third Ta site, Ta(3) is bonded in a 3-coordinate geometry to three equivalent Al(6) and three equivalent C(3) atoms. All Ta(3)-Al(6) bond lengths are 2.88 Å. All Ta(3)-C(3) bond lengths are 2.17 Å. In the fourth Ta site, Ta(4) is bonded in a 3-coordinate geometry to three equivalent Al(1) and three equivalent C(1) atoms. All Ta(4)-Al(1) bond lengths are 2.84 Å. All Ta(4)-C(1) bond lengths are 2.16 Å. There are eight inequivalent V sites. In the first V site, V(1) is bonded in a 3-coordinate geometry to three equivalent Al(2) and three equivalent C(2) atoms. All V(1)-Al(2) bond lengths are 2.78 Å. All V(1)-C(2) bond lengths are 2.04 Å. In the second V site, V(2) is bonded in a 3-coordinate geometry to three equivalent Al(3) and three equivalent C(3) atoms. All V(2)-Al(3) bond lengths are 2.78 Å. All V(2)-C(3) bond lengths are 2.04 Å. In the third V site, V(3) is bonded in a 3-coordinate geometry to three equivalent Al(1) and three equivalent C(4) atoms. All V(3)-Al(1) bond lengths are 2.72 Å. All V(3)-C(4) bond lengths are 2.04 Å. In the fourth V site, V(4) is bonded in a 3-coordinate geometry to three equivalent Al(2) and three equivalent C(5) atoms. All V(4)-Al(2) bond lengths are 2.77 Å. All V(4)-C(5) bond lengths are 2.05 Å. In the fifth V site, V(5) is bonded in a 3-coordinate geometry to three equivalent Al(3) and three equivalent C(6) atoms. All V(5)-Al(3) bond lengths are 2.78 Å. All V(5)-C(6) bond lengths are 2.04 Å. In the sixth V site, V(6) is bonded in a 3-coordinate geometry to three equivalent Al(4) and three equivalent C(5) atoms. All V(6)-Al(4) bond lengths are 2.72 Å. All V(6)-C(5) bond lengths are 2.04 Å. In the seventh V site, V(7) is bonded in a 3-coordinate geometry to three equivalent Al(5) and three equivalent C(6) atoms. All V(7)-Al(5) bond lengths are 2.75 Å. All V(7)-C(6) bond lengths are 2.04 Å. In the eighth V site, V(8) is bonded in a 3-coordinate geometry to three equivalent Al(6) and three equivalent C(4) atoms. All V(8)-Al(6) bond lengths are 2.74 Å. All V(8)-C(4) bond lengths are 2.04 Å. There are six inequivalent Al sites. In the first Al site, Al(1) is bonded to three equivalent Ta(4), three equivalent V(3), and six equivalent Al(1) atoms to form distorted AlTa3Al6V3 cuboctahedra that share corners with six equivalent Al(1)Ta3Al6V3 cuboctahedra, corners with three equivalent C(1)Ta6 octahedra, corners with three equivalent C(4)V6 octahedra, edges with six equivalent Al(1)Ta3Al6V3 cuboctahedra, edges with three equivalent C(1)Ta6 octahedra, edges with three equivalent C(4)V6 octahedra, and faces with six equivalent Al(1)Ta3Al6V3 cuboctahedra. The corner-sharing octahedral tilt angles range from 16-19°. All Al(1)-Al(1) bond lengths are 2.99 Å. In the second Al site, Al(2) is bonded to three equivalent V(1), three equivalent V(4), and six equivalent Al(2) atoms to form AlAl6V6 cuboctahedra that share corners with six equivalent Al(2)Al6V6 cuboctahedra, corners with three equivalent C(2)Ta3V3 octahedra, corners with three equivalent C(5)V6 octahedra, edges with six equivalent Al(2)Al6V6 cuboctahedra, edges with three equivalent C(2)Ta3V3 octahedra, edges with three equivalent C(5)V6 octahedra, and faces with six equivalent Al(2)Al6V6 cuboctahedra. The corner-sharing octahedral tilt angles range from 19-20°. All Al(2)-Al(2) bond lengths are 2.99 Å. In the third Al site, Al(3) is bonded to three equivalent V(2), three equivalent V(5), and six equivalent Al(3) atoms to form AlAl6V6 cuboctahedra that share corners with six equivalent Al(3)Al6V6 cuboctahedra, corners with three equivalent C(3)Ta3V3 octahedra, corners with three equivalent C(6)V6 octahedra, edges with six equivalent Al(3)Al6V6 cuboctahedra, edges with three equivalent C(3)Ta3V3 octahedra, edges with three equivalent C(6)V6 octahedra, and faces with six equivalent Al(3)Al6V6 cuboctahedra. The corner-sharing octahedral tilt angles range from 19-20°. All Al(3)-Al(3) bond lengths are 2.99 Å. In the fourth Al site, Al(4) is bonded to three equivalent Ta(1), three equivalent V(6), and six equivalent Al(4) atoms to form distorted AlTa3Al6V3 cuboctahedra that share corners with six equivalent Al(4)Ta3Al6V3 cuboctahedra, corners with three equivalent C(1)Ta6 octahedra, corners with three equivalent C(5)V6 octahedra, edges with six equivalent Al(4)Ta3Al6V3 cuboctahedra, edges with three equivalent C(1)Ta6 octahedra, edges with three equivalent C(5)V6 octahedra, and faces with six equivalent Al(4)Ta3Al6V3 cuboctahedra. The corner-sharing octahedral tilt angles range from 16-18°. All Al(4)-Al(4) bond lengths are 2.99 Å. In the fifth Al site, Al(5) is bonded to three equivalent Ta(2), three equivalent V(7), and six equivalent Al(5) atoms to form AlTa3Al6V3 cuboctahedra that share corners with six equivalent Al(5)Ta3Al6V3 cuboctahedra, corners with three equivalent C(2)Ta3V3 octahedra, corners with three equivalent C(6)V6 octahedra, edges with six equivalent Al(5)Ta3Al6V3 cuboctahedra, edges with three equivalent C(2)Ta3V3 octahedra, edges with three equivalent C(6)V6 octahedra, and faces with six equivalent Al(5)Ta3Al6V3 cuboctahedra. The corner-sharing octahedral tilt angles range from 16-19°. All Al(5)-Al(5) bond lengths are 2.99 Å. In the sixth Al site, Al(6) is bonded to three equivalent Ta(3), three equivalent V(8), and six equivalent Al(6) atoms to form distorted AlTa3Al6V3 cuboctahedra that share corners with six equivalent Al(6)Ta3Al6V3 cuboctahedra, corners with three equivalent C(3)Ta3V3 octahedra, corners with three equivalent C(4)V6 octahedra, edges with six equivalent Al(6)Ta3Al6V3 cuboctahedra, edges with three equivalent C(3)Ta3V3 octahedra, edges with three equivalent C(4)V6 octahedra, and faces with six equivalent Al(6)Ta3Al6V3 cuboctahedra. The corner-sharing octahedral tilt angles range from 16-19°. All Al(6)-Al(6) bond lengths are 2.99 Å. There are six inequivalent C sites. In the first C site, C(1) is bonded to three equivalent Ta(1) and three equivalent Ta(4) atoms to form CTa6 octahedra that share corners with three equivalent Al(1)Ta3Al6V3 cuboctahedra, corners with three equivalent Al(4)Ta3Al6V3 cuboctahedra, edges with three equivalent Al(1)Ta3Al6V3 cuboctahedra, edges with three equivalent Al(4)Ta3Al6V3 cuboctahedra, and edges with six equivalent C(1)Ta6 octahedra. In the second C site, C(2) is bonded to three equivalent Ta(2) and three equivalent V(1) atoms to form CTa3V3 octahedra that share corners with three equivalent Al(2)Al6V6 cuboctahedra, corners with three equivalent Al(5)Ta3Al6V3 cuboctahedra, edges with three equivalent Al(2)Al6V6 cuboctahedra, edges with three equivalent Al(5)Ta3Al6V3 cuboctahedra, and edges with six equivalent C(2)Ta3V3 octahedra. In the third C site, C(3) is bonded to three equivalent Ta(3) and three equivalent V(2) atoms to form CTa3V3 octahedra that share corners with three equivalent Al(3)Al6V6 cuboctahedra, corners with three equivalent Al(6)Ta3Al6V3 cuboctahedra, edges with three equivalent Al(3)Al6V6 cuboctahedra, edges with three equivalent Al(6)Ta3Al6V3 cuboctahedra, and edges with six equivalent C(3)Ta3V3 octahedra. In the fourth C site, C(4) is bonded to three equivalent V(3) and three equivalent V(8) atoms to form CV6 octahedra that share corners with three equivalent Al(1)Ta3Al6V3 cuboctahedra, corners with three equivalent Al(6)Ta3Al6V3 cuboctahedra, edges with three equivalent Al(1)Ta3Al6V3 cuboctahedra, edges with three equivalent Al(6)Ta3Al6V3 cuboctahedra, and edges with six equivalent C(4)V6 octahedra. In the fifth C site, C(5) is bonded to three equivalent V(4) and three equivalent V(6) atoms to form CV6 octahedra that share corners with three equivalent Al(2)Al6V6 cuboctahedra, corners with three equivalent Al(4)Ta3Al6V3 cuboctahedra, edges with three equivalent Al(2)Al6V6 cuboctahedra, edges with three equivalent Al(4)Ta3Al6V3 cuboctahedra, and edges with six equivalent C(5)V6 octahedra. In the sixth C site, C(6) is bonded to three equivalent V(5) and three equivalent V(7) atoms to form CV6 octahedra that share corners with three equivalent Al(3)Al6V6 cuboctahedra, corners with three equivalent Al(5)Ta3Al6V3 cuboctahedra, edges with three equivalent Al(3)Al6V6 cuboctahedra, edges with three equivalent Al(5)Ta3Al6V3 cuboctahedra, and edges with six equivalent C(6)V6 octahedra.