Materials Data on Hf(Nb2B3)4 by Materials Project

Abstract

Hf(Nb2B3)4 crystallizes in the orthorhombic Immm space group. The structure is three-dimensional. Hf4+ is bonded to twelve B2- atoms to form a mixture of edge and face-sharing HfB12 cuboctahedra. There are eight shorter (2.48 Å) and four longer (2.53 Å) Hf–B bond lengths. There are four inequivalent Nb+2.50+ sites. In the first Nb+2.50+ site, Nb+2.50+ is bonded in a 7-coordinate geometry to seven B2- atoms. There are a spread of Nb–B bond distances ranging from 2.40–2.58 Å. In the second Nb+2.50+ site, Nb+2.50+ is bonded in a 7-coordinate geometry to seven B2- atoms. There are a spread of Nb–B bond distances ranging from 2.39–2.59 Å. In the third Nb+2.50+ site, Nb+2.50+ is bonded in a 7-coordinate geometry to seven B2- atoms. There are a spread of Nb–B bond distances ranging from 2.39–2.58 Å. In the fourth Nb+2.50+ site, Nb+2.50+ is bonded to twelve B2- atoms to form a mixture of edge and face-sharing NbB12 cuboctahedra. There are eight shorter (2.48 Å) and four longer (2.51 Å) Nb–B bond lengths. There are six inequivalent B2- sites. In the first B2- site, B2- is bonded in a 9-coordinate geometry to six Nb+2.50+ and three B2- atoms. There is one shorter (1.82 Å) and two longer (1.85 Å) B–B bond length. In the second B2- site, B2- is bonded in a 9-coordinate geometry to six Nb+2.50+ and three B2- atoms. Both B–B bond lengths are 1.85 Å. In the third B2- site, B2- is bonded in a 9-coordinate geometry to four equivalent Hf4+, two equivalent Nb+2.50+, and three B2- atoms. There is one shorter (1.84 Å) and two longer (1.85 Å) B–B bond length. In the fourth B2- site, B2- is bonded in a 9-coordinate geometry to seven Nb+2.50+ and two equivalent B2- atoms. In the fifth B2- site, B2- is bonded in a 9-coordinate geometry to seven Nb+2.50+ and two equivalent B2- atoms. In the sixth B2- site, B2- is bonded in a 9-coordinate geometry to two equivalent Hf4+, five Nb+2.50+, and two equivalent B2- atoms.