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Materials Data on Nb5Ge2B by Materials Project

Nb5BGe2 crystallizes in the tetragonal I4/mcm space group. The structure is three-dimensional. there are two inequivalent Nb sites. In the first Nb site, Nb is bonded to two equivalent B and four equivalent Ge atoms to form distorted corner-sharing NbGe4B2 octahedra. The corner-sharing octahedra tilt angles range from 0–50°. Both Nb–B bond lengths are 3.00 Å. All Nb–Ge bond lengths are 2.56 Å. In the second Nb site, Nb is bonded in a 5-coordinate geometry to two equivalent B and three equivalent Ge atoms. Both Nb–B bond lengths are 2.68 Å. There are one shorter (2.65 Å) and two longer (2.74 Å) Nb–Ge bond lengths. B is bonded in a 10-coordinate geometry to ten Nb atoms. Ge is bonded in a 9-coordinate geometry to eight Nb and one Ge atom. The Ge–Ge bond length is 2.47 Å.

36 MATERIALS SCIENCE↗

Materials Data on Nb5Ge3B by Materials Project

Nb5BGe3 crystallizes in the hexagonal P6_3/mcm space group. The structure is three-dimensional. there are two inequivalent Nb sites. In the first Nb site, Nb is bonded in a 6-coordinate geometry to six equivalent Ge atoms. All Nb–Ge bond lengths are 2.73 Å. In the second Nb site, Nb is bonded in a 7-coordinate geometry to two equivalent B and five equivalent Ge atoms. Both Nb–B bond lengths are 2.32 Å. There are a spread of Nb–Ge bond distances ranging from 2.72–2.95 Å. B is bonded to six equivalent Nb atoms to form face-sharing BNb6 octahedra. Ge is bonded in a 9-coordinate geometry to nine Nb atoms.

36 MATERIALS SCIENCE↗