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DOE OSTI2017

Materials Data on NbBW by Materials Project

NbWB is half-Heusler structured and crystallizes in the cubic F-43m space group. The structure is three-dimensional. Nb is bonded in a body-centered cubic geometry to four equivalent W and four equivalent B atoms. All Nb–W bond lengths are 2.55 Å. All Nb–B bond lengths are 2.55 Å. W is bonded to four equivalent Nb and six equivalent B atoms to form distorted WNb4B6 tetrahedra that share corners with four equivalent BNb4W6 tetrahedra, corners with six equivalent WNb4B6 tetrahedra, edges with six equivalent BNb4W6 tetrahedra, and faces with twelve equivalent WNb4B6 tetrahedra. All W–B bond lengths are 2.95 Å. B is bonded to four equivalent Nb and six equivalent W atoms to form distorted BNb4W6 tetrahedra that share corners with four equivalent WNb4B6 tetrahedra, corners with six equivalent BNb4W6 tetrahedra, edges with six equivalent WNb4B6 tetrahedra, and faces with twelve equivalent BNb4W6 tetrahedra.

36 MATERIALS SCIENCE↗

DOE OSTI2020

Materials Data on Nb3B4W3 by Materials Project

Nb3W3B4 crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. there are two inequivalent Nb2+ sites. In the first Nb2+ site, Nb2+ is bonded in a square co-planar geometry to four B3- atoms. There are a spread of Nb–B bond distances ranging from 2.47–2.52 Å. In the second Nb2+ site, Nb2+ is bonded in a distorted hexagonal planar geometry to six B3- atoms. There are four shorter (2.44 Å) and two longer (2.50 Å) Nb–B bond lengths. There are two inequivalent W2+ sites. In the first W2+ site, W2+ is bonded in a distorted hexagonal planar geometry to six B3- atoms. There are four shorter (2.41 Å) and two longer (2.49 Å) W–B bond lengths. In the second W2+ site, W2+ is bonded in a hexagonal planar geometry to six B3- atoms. There are four shorter (2.39 Å) and two longer (2.47 Å) W–B bond lengths. There are three inequivalent B3- sites. In the first B3- site, B3- is bonded in a 9-coordinate geometry to two equivalent Nb2+, six W2+, and one B3- atom. The B–B bond length is 1.90 Å. In the second B3- site, B3- is bonded in a 9-coordinate geometry to four Nb2+, four equivalent W2+, and one B3- atom. In the third B3- site, B3- is bonded in a 9-coordinate geometry to four Nb2+, four W2+, and one B3- atom. The B–B bond length is 1.95 Å.

36 MATERIALS SCIENCE↗

DOE OSTI2020

Materials Data on NbB2W by Materials Project

NbWB2 crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. Nb4+ is bonded in a 7-coordinate geometry to seven B3- atoms. There are a spread of Nb–B bond distances ranging from 2.39–2.54 Å. W2+ is bonded in a 7-coordinate geometry to seven B3- atoms. There are six shorter (2.37 Å) and one longer (2.60 Å) W–B bond lengths. There are two inequivalent B3- sites. In the first B3- site, B3- is bonded in a 9-coordinate geometry to three equivalent Nb4+, four equivalent W2+, and two equivalent B3- atoms. Both B–B bond lengths are 1.87 Å. In the second B3- site, B3- is bonded in a 9-coordinate geometry to four equivalent Nb4+, three equivalent W2+, and two equivalent B3- atoms.

36 MATERIALS SCIENCE↗