Cross-conjugation increases the conductance of meta-connected fluorenones

Charge transport is strongly suppressed by destructive quantum interference (DQI) in meta-connected 1,1′-biphenyl-containing molecules, resulting in low electrical conductance. Surprisingly, we have found that DQI is almost entirely overcome by adding a bridging carbonyl, to yield a cross-conjugated fluorenone. This contrasts with other π-systems, such as para-connected anthraquinone, where cross-conjugation results in low conductance.