 It can be summarised by the formula (CO)3Co(μ-CO)2Co(CO)3 and has C2v symmetry.This structure resembles diiron nonacarbonyl (Fe2(CO)9) but with one fewer bridging carbonyl.The Co–Co distance is 2.52 Å, and the Co–COterminal and Co–CObridge distances are 1.80 and 1.90 Å, respectively.