Materials Data on Ta3B4 by Materials Project
Ta3B4 crystallizes in the orthorhombic Immm space group. The structure is three-dimensional. there are two inequivalent Ta4+ sites. In the first Ta4+ site, Ta4+ is bonded to twelve B3- atoms to form a mixture of edge and face-sharing TaB12 cuboctahedra. There are eight shorter (2.46 Å) and four longer (2.50 Å) Ta–B bond lengths. In the second Ta4+ site, Ta4+ is bonded in a 7-coordinate geometry to seven B3- atoms. There are a spread of Ta–B bond distances ranging from 2.37–2.55 Å. There are two inequivalent B3- sites. In the first B3- site, B3- is bonded in a 9-coordinate geometry to seven Ta4+ and two equivalent B3- atoms. Both B–B bond lengths are 1.85 Å. In the second B3- site, B3- is bonded in a 9-coordinate geometry to six Ta4+ and three B3- atoms. The B–B bond length is 1.81 Å.