The three-dimensional structure of 3,3′,4,4′-tetrachlorobiphenyl, a dioxin-like polychlorinated biphenyl (PCB)

The crystal structure of PCB 77 (3,3′,4,4′-tetrachlorobiphenyl, C12H6Cl4), a dioxin-like PCB congener, is described. The dihedral angle of PCB 77 is 43.94(6)°, which is slightly larger than calculated or experimental dihedral angles of biphenyl derivatives in solution but smaller than experimental dihedral angles in the gas phase.