Materials Data on BC7 by Materials Project

Abstract

BC7 crystallizes in the orthorhombic Pmm2 space group. The structure is three-dimensional. B3+ is bonded to four C+0.43- atoms to form BC4 tetrahedra that share corners with two equivalent BC4 tetrahedra and corners with ten CC4 tetrahedra. There is two shorter (1.60 Å) and two longer (1.67 Å) B–C bond length. There are five inequivalent C+0.43- sites. In the first C+0.43- site, C+0.43- is bonded to one B3+ and three C+0.43- atoms to form distorted corner-sharing CBC3 tetrahedra. There is two shorter (1.54 Å) and one longer (1.55 Å) C–C bond length. In the second C+0.43- site, C+0.43- is bonded to two equivalent B3+ and two equivalent C+0.43- atoms to form distorted corner-sharing CB2C2 tetrahedra. Both C–C bond lengths are 1.53 Å. In the third C+0.43- site, C+0.43- is bonded to four C+0.43- atoms to form corner-sharing CC4 tetrahedra. There is two shorter (1.54 Å) and two longer (1.58 Å) C–C bond length. In the fourth C+0.43- site, C+0.43- is bonded to four C+0.43- atoms to form CC4 tetrahedra that share corners with two equivalent BC4 tetrahedra and corners with ten CC4 tetrahedra. In the fifth C+0.43- site, C+0.43- is bonded to four C+0.43- atoms to form CC4 tetrahedra that share corners with four equivalent BC4 tetrahedra and corners with eight CC4 tetrahedra.