Materials Data on AlW3C4 by Materials Project

Abstract

W3AlC4 is Tungsten Carbide-derived structured and crystallizes in the orthorhombic Pmm2 space group. The structure is three-dimensional. there are three inequivalent W+4.33+ sites. In the first W+4.33+ site, W+4.33+ is bonded to six C4- atoms to form distorted WC6 pentagonal pyramids that share corners with four equivalent AlC6 pentagonal pyramids, corners with eight WC6 pentagonal pyramids, edges with two equivalent AlC6 pentagonal pyramids, edges with four WC6 pentagonal pyramids, and faces with two equivalent WC6 pentagonal pyramids. There are four shorter (2.19 Å) and two longer (2.20 Å) W–C bond lengths. In the second W+4.33+ site, W+4.33+ is bonded to six C4- atoms to form a mixture of distorted corner, edge, and face-sharing WC6 pentagonal pyramids. There are two shorter (2.20 Å) and four longer (2.21 Å) W–C bond lengths. In the third W+4.33+ site, W+4.33+ is bonded to six C4- atoms to form distorted WC6 pentagonal pyramids that share corners with four equivalent AlC6 pentagonal pyramids, corners with eight WC6 pentagonal pyramids, edges with two equivalent AlC6 pentagonal pyramids, edges with four WC6 pentagonal pyramids, and faces with two equivalent WC6 pentagonal pyramids. There are two shorter (2.15 Å) and four longer (2.21 Å) W–C bond lengths. Al3+ is bonded to six C4- atoms to form distorted AlC6 pentagonal pyramids that share corners with four equivalent AlC6 pentagonal pyramids, corners with eight WC6 pentagonal pyramids, edges with two equivalent AlC6 pentagonal pyramids, edges with four WC6 pentagonal pyramids, and faces with two equivalent AlC6 pentagonal pyramids. There are four shorter (2.19 Å) and two longer (2.36 Å) Al–C bond lengths. There are four inequivalent C4- sites. In the first C4- site, C4- is bonded to six W+4.33+ atoms to form a mixture of distorted corner, edge, and face-sharing CW6 pentagonal pyramids. In the second C4- site, C4- is bonded to six W+4.33+ atoms to form a mixture of distorted corner, edge, and face-sharing CW6 pentagonal pyramids. In the third C4- site, C4- is bonded in a 6-coordinate geometry to two equivalent W+4.33+ and four equivalent Al3+ atoms. In the fourth C4- site, C4- is bonded to four equivalent W+4.33+ and two equivalent Al3+ atoms to form distorted CAl2W4 pentagonal pyramids that share corners with eight CW6 pentagonal pyramids, edges with four CW6 pentagonal pyramids, and faces with two equivalent CAl2W4 pentagonal pyramids.