PMID- 14531709
OWN - NLM
STAT- PubMed-not-MEDLINE
DCOM- 20031215
LR  - 20031008
IS  - 0002-7863 (Print)
IS  - 0002-7863 (Linking)
VI  - 125
IP  - 41
DP  - 2003 Oct 15
TI  - Single-molecule spectroscopy of interfacial electron transfer.
PG  - 12649-54
AB  - It is widely appreciated that single-molecule spectroscopy (SMS) can be used to 
      measure properties of individual molecules which would normally be obscured in an 
      ensemble-averaged measurement. In this report we show how SMS can be used to 
      measure photoinduced interfacial electron transfer (IET) and back electron 
      transfer rates in a prototypical chromophore-bridge-electrode nonadiabatic 
      electron transfer system. 
      N-(1-hexylheptyl)-N'-(12-carboxylicdodecyl)perylene-3,4,9,10-tetracarboxylbisimide 
      was synthesized and incorporated into mixed self-assembled monolayers (SAMs) on 
      an ITO (tin-doped indium oxide, a p-type semiconductor) electrode. 
      Single-molecule fluorescence time trajectories from this system reveals "blinks", 
      momentary losses in fluorescence (>20 ms to seconds in duration), which are 
      attributed to discrete electron transfer events: electron injection from the 
      perylene chromophore into the conduction band of the ITO leads to the loss of 
      fluorescence, and charge recombination (back electron transfer) leads to the 
      return of fluorescence. Such blinks are not observed when an electrode is not 
      present. The fluorescence trajectories were analyzed to obtain the forward and 
      back electron rates; the measured rates are found to lie in the millisecond to 
      second regime. Different rates are observed for different molecules, but the 
      lifetime distributions for the forward or back electron transfer for any given 
      molecule are well fit by single exponential kinetics. The methodology used is 
      applicable to a wide variety of systems and can be used to study the effects of 
      distance, orientation, linker, environment, etc. on electron transfer rates. The 
      results and methodology have implications for molecular electronics, where 
      understanding and controlling the range of possible behaviors inherent to 
      molecular systems will likely be as important as understanding the individual 
      behavior of any given molecule.
FAU - Holman, Michael W
AU  - Holman MW
AD  - Department of Chemistry, Columbia University, 3000 Broadway, New York, New York 
      10027, USA.
FAU - Liu, Ruchuan
AU  - Liu R
FAU - Adams, David M
AU  - Adams DM
LA  - eng
PT  - Journal Article
PL  - United States
TA  - J Am Chem Soc
JT  - Journal of the American Chemical Society
JID - 7503056
EDAT- 2003/10/09 05:00
MHDA- 2003/10/09 05:01
CRDT- 2003/10/09 05:00
PHST- 2003/10/09 05:00 [pubmed]
PHST- 2003/10/09 05:01 [medline]
PHST- 2003/10/09 05:00 [entrez]
AID - 10.1021/ja0343104 [doi]
PST - ppublish
SO  - J Am Chem Soc. 2003 Oct 15;125(41):12649-54. doi: 10.1021/ja0343104.