BaC2 is Magnesium tetraboride-like structured and crystallizes in the orthorhombic Pnma space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 9-coordinate geometry to two equivalent C(2), three equivalent C(1), and four equivalent C(3) atoms. In the second Ba site, Ba(2) is bonded in a 10-coordinate geometry to one C(1), three equivalent C(2), and six equivalent C(3) atoms. There are three inequivalent C sites. In the first C site, C(1) is bonded in a 7-coordinate geometry to one Ba(2), three equivalent Ba(1), one C(2), and two equivalent C(3) atoms. In the second C site, C(2) is bonded in a 8-coordinate geometry to two equivalent Ba(1), three equivalent Ba(2), one C(1), and two equivalent C(3) atoms. In the third C site, C(3) is bonded in a 8-coordinate geometry to two equivalent Ba(1), three equivalent Ba(2), one C(1), one C(2), and one C(3) atom.
BaC2 is Magnesium tetraboride-like structured and crystallizes in the orthorhombic Pnma space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 9-coordinate geometry to two equivalent C(2), three equivalent C(1), and four equivalent C(3) atoms. There is one shorter (2.86 Å) and one longer (3.49 Å) Ba(1)-C(2) bond length. There is one shorter (2.85 Å) and two longer (3.06 Å) Ba(1)-C(1) bond lengths. There are two shorter (3.03 Å) and two longer (3.15 Å) Ba(1)-C(3) bond lengths. In the second Ba site, Ba(2) is bonded in a 10-coordinate geometry to one C(1), three equivalent C(2), and six equivalent C(3) atoms. The Ba(2)-C(1) bond length is 3.05 Å. There is one shorter (2.93 Å) and two longer (2.97 Å) Ba(2)-C(2) bond lengths. There are a spread of Ba(2)-C(3) bond distances ranging from 2.87-3.07 Å. There are three inequivalent C sites. In the first C site, C(1) is bonded in a 7-coordinate geometry to one Ba(2), three equivalent Ba(1), one C(2), and two equivalent C(3) atoms. The C(1)-C(2) bond length is 1.56 Å. Both C(1)-C(3) bond lengths are 1.56 Å. In the second C site, C(2) is bonded in a 8-coordinate geometry to two equivalent Ba(1), three equivalent Ba(2), one C(1), and two equivalent C(3) atoms. Both C(2)-C(3) bond lengths are 1.57 Å. In the third C site, C(3) is bonded in a 8-coordinate geometry to two equivalent Ba(1), three equivalent Ba(2), one C(1), one C(2), and one C(3) atom. The C(3)-C(3) bond length is 1.57 Å.