Binuclear butadiene chromium carbonyls: Comparison with their trimethylenemethane isomers

The structures and energetics of the butadiene chromium carbonyl complexes (C4H6)Cr(CO)m (m = 5, 4, 3, 2) and (C4H6)2Cr2(CO)n (n = 7, 6, 5) have been investigated by the B3LYP and BP86 methods. The (C4H6)2Cr2(CO)n (n = 7, 6, 5) structures are similar to the previously reported isomeric trimethylenemethane [(CH2)3C]2Cr2(CO)n structures except for some differences in the arrangements of the bridging carbonyl groups.