Electron transfer from excited dye molecules (chlorophyll or fluorescein) to a semiconductor is demonstrated by photoaction and photoluminescence spectra on field‐effect transistors consisting of dye‐sensitized individual SnO2 nanowires. The photoaction spectrum shows a much better resolution for nanowires non‐covalently functionalized with dye molecules than for dyes deposited on SnO2 nanoparticle‐films. Possible reasons for the deviation between the photoaction spectra and ordinary optical absorption spectra as well as for the current‐tail appearing along the falling edge are addressed. In dye‐sensitized nanowires, electron transfer from photo‐excited dyes to nanowires is analyzed by comparing gate‐voltage dependences in photoaction and photoluminescence spectra. The importance of this study is in the understanding of electron injection and recombination provided, as well as the performance optimization of nanowire‐based dye‐sensitized solar cells.

The vibronic spectra of allyl-h5 (CH2CHCH2) and allyl-d5 (CD2CDCD2) radicals at 6.0–8.2 eV have been observed using 2+1 resonance-enhanced multiphoton ionization (REMPI) spectroscopy. The allyl-h5 and allyl-d5 radicals were produced in the nozzle of a supersonic jet expansion by the pyrolysis of CH2CHCH2I and CD2CDCD2Br, respectively. Together with our previous study, Rydberg states of ns (n=4–12) for allyl-h5 and (n=4–10) for allyl-d5 have been observed in the REMPI spectra. Prominent vibrational progressions with the spacings of ∼440 cm−1 in allyl-h5 and ∼360 cm−1 in allyl-d5 are observed in the s Rydberg series. The totally symmetric ∠CCC-bending mode is responsible for the vibrational progressions. Facilitated with ab initio calculated Franck–Condon factors, other vibrations (CH2 rocking and C3 stretching) observed in the s Rydberg series have also been identified. The adiabatic ionization energies, 65 594±9 cm−1 (8.133±0.001 eV) for allyl-h5 and 65 527±16 cm−1 (8.124±0.002 eV) for allyl-d5, are extrapolated from the convergence of the observed ns Rydberg series.

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