CaC2 crystallizes in the orthorhombic Immm space group. Ca(1) is bonded in a 10-coordinate geometry to four equivalent C(2) and six equivalent C(1) atoms. There are two inequivalent C sites. In the first C site, C(1) is bonded in a 8-coordinate geometry to six equivalent Ca(1) and two equivalent C(2) atoms. In the second C site, C(2) is bonded in a 3-coordinate geometry to four equivalent Ca(1), one C(2), and two equivalent C(1) atoms.
CaC2 crystallizes in the orthorhombic Immm space group. Ca(1) is bonded in a 10-coordinate geometry to four equivalent C(2) and six equivalent C(1) atoms. All Ca(1)-C(2) bond lengths are 2.65 Å. There are two shorter (2.64 Å) and four longer (2.67 Å) Ca(1)-C(1) bond lengths. There are two inequivalent C sites. In the first C site, C(1) is bonded in a 8-coordinate geometry to six equivalent Ca(1) and two equivalent C(2) atoms. Both C(1)-C(2) bond lengths are 1.55 Å. In the second C site, C(2) is bonded in a 3-coordinate geometry to four equivalent Ca(1), one C(2), and two equivalent C(1) atoms. The C(2)-C(2) bond length is 1.46 Å.