On the structure of m-benzynes

The question of the structure of m-benzynes is discussed in light of recent theoretical and experimental results. The calculated density functional IR spectrum (B3LYP) of tetrafluoro-m-benzyne is reported and compared with the experiment. It is concluded that without additional experiments and possibly calculations the question of whether m-benzynes exist as a closed shell bicyclic or open shell monocyclic structures cannot yet be definitely answered.