Nitro End-Groups: Remarkable Vibrational Reporters for Charge Transfer in the Excited States of Oligo(p-Phenyleneethynylene)-Bridged Donor-Acceptor Dyads

The D-π-A dyads [(n-Hex)2N(1,4-C6H4)]C≡C[(1,4-C6H4)NO2] (1) and [(n-Hex)2N(1,4-C6H4)]C≡C(1,4-C6H4)C≡C[(1,4-C6H4)NO2] (2) have been studied by ultrafast time-resolved infrared absorption spectroscop...