DOE OSTI2020
BaC2 is Magnesium tetraboride-like structured and crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are two inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a 9-coordinate geometry to nine C1- atoms. There are a spread of Ba–C bond distances ranging from 2.85–3.49 Å. In the second Ba2+ site, Ba2+ is bonded in a 10-coordinate geometry to ten C1- atoms. There are a spread of Ba–C bond distances ranging from 2.87–3.07 Å. There are three inequivalent C1- sites. In the first C1- site, C1- is bonded in a 7-coordinate geometry to four Ba2+ and three C1- atoms. All C–C bond lengths are 1.56 Å. In the second C1- site, C1- is bonded in a 8-coordinate geometry to five Ba2+ and three C1- atoms. Both C–C bond lengths are 1.57 Å. In the third C1- site, C1- is bonded in a 8-coordinate geometry to five Ba2+ and three C1- atoms. The C–C bond length is 1.57 Å.