Electron Tunneling Through Organic Molecules in Frozen Glasses
10.1126/science.1103818
Crossref journal-article
American Association for the Advancement of Science (AAAS)
Science (221)
Abstract

Reaction rates extracted from measurements of donor luminescence quenching by randomly dispersed electron acceptors reveal an exponential decay constant of 1.23 per angstrom for electron tunneling through a frozen toluene glass (with a barrier to tunneling of 1.4 electron volts). The decay constant is 1.62 per angstrom (the barrier, 2.6 electron volts) in a frozen 2-methyl-tetrahydrofuran glass. Comparison to decay constants for tunneling across covalently linked xylyl (0.76 per angstrom) and alkyl (1.0 per angstrom) bridges leads to the conclusion that tunneling between solvent molecules separated by ∼2 angstroms (van der Waals contact) is 20 to 50 times slower than tunneling through a comparable length of a covalently bonded bridge. Our results provide experimental confirmation that covalently bonded pathways can facilitate electron flow through folded polypeptide structures.

Bibliography

Wenger, O. S., Leigh, B. S., Villahermosa, R. M., Gray, H. B., & Winkler, J. R. (2005). Electron Tunneling Through Organic Molecules in Frozen Glasses. Science, 307(5706), 99–102.

Authors 5
  1. Oliver S. Wenger (first)
  2. Brian S. Leigh (additional)
  3. Randy M. Villahermosa (additional)
  4. Harry B. Gray (additional)
  5. Jay R. Winkler (additional)
References 47 Referenced 142
  1. L. Esaki, Science183, 1149 (1974). (10.1126/science.183.4130.1149) / Science (1974)
  2. J. R. Miller, J. Phys. Chem.79, 1070 (1975). (10.1021/j100578a007) / J. Phys. Chem. (1975)
  3. D. De Vault, J. H. Parkes, B. Chance, Nature215, 642 (1967). (10.1038/215642a0) / Nature (1967)
  4. 10.1017/S0033583503003913
  5. H. M. McConnell, J. Chem. Phys.35, 508 (1961). (10.1063/1.1731961) / J. Chem. Phys. (1961)
  6. J. Halpern, L. E. Orgel, Disc. Faraday Soc.1960, 32 (1960). / Disc. Faraday Soc. (1960)
  7. S. S. Skourtis, D. N. Beratan, Adv. Chem. Phys.106, 377 (1999). / Adv. Chem. Phys. (1999)
  8. H. Oevering et al., J. Am. Chem. Soc.109, 3258 (1987). (10.1021/ja00245a014) / J. Am. Chem. Soc. (1987)
  9. M. D. Johnson, J. R. Miller, N. S. Green, G. L. Closs, J. Phys. Chem.93, 1173 (1989). (10.1021/j100341a001) / J. Phys. Chem. (1989)
  10. J. F. Smalley et al., J. Am. Chem. Soc.125, 2004 (2003). (10.1021/ja028458j) / J. Am. Chem. Soc. (2003)
  11. A. Helms, D. Heiler, G. McLendon, J. Am. Chem. Soc.114, 6227 (1992). (10.1021/ja00041a047) / J. Am. Chem. Soc. (1992)
  12. R. Villahermosa thesis California Institute of Technology (2002).
  13. W. B. Davis, W. A. Svec, M. A. Ratner, M. R. Wasielewski, Nature396, 60 (1998). (10.1038/23912) / Nature (1998)
  14. F. D. Lewis et al., Proc. Natl. Acad. Sci. U.S.A.99, 12536 (2002). (10.1073/pnas.192432899) / Proc. Natl. Acad. Sci. U.S.A. (2002)
  15. 10.1126/science.256.5059.1007
  16. 10.1126/science.7792598
  17. 10.1146/annurev.bi.65.070196.002541
  18. J. N. Onuchic, D. N. Beratan, J. R. Winkler, H. B. Gray, Annu. Rev. Biophys. Biomol. Struct.21, 349 (1992). (10.1146/annurev.bb.21.060192.002025) / Annu. Rev. Biophys. Biomol. Struct. (1992)
  19. K. Kumar, I. V. Kurnikov, D. N. Beratan, D. H. Waldeck, M. B. Zimmt, J. Phys. Chem. A102, 5529 (1998). (10.1021/jp980113t) / J. Phys. Chem. A (1998)
  20. K. Weidemaier, H. L. Tavernier, S. F. Swallen, M. D. Fayer, J. Phys. Chem. A101, 1887 (1997). (10.1021/jp962973k) / J. Phys. Chem. A (1997)
  21. L. Burel, M. Mostafavi, S. Murata, M. Tachiya, J. Phys. Chem. A103, 5882 (1999). (10.1021/jp991087h) / J. Phys. Chem. A (1999)
  22. J. R. Miller, J. A. Peeples, M. J. Schmitt, G. L. Closs, J. Am. Chem. Soc.104, 6488 (1982). (10.1021/ja00388a002) / J. Am. Chem. Soc. (1982)
  23. R. C. Dorfman, Y. Lin, M. D. Fayer, J. Phys. Chem.93, 6388 (1989). (10.1021/j100354a023) / J. Phys. Chem. (1989)
  24. T. Guarr, M. E. McGuire, G. McLendon, J. Am. Chem. Soc.107, 5104 (1985). (10.1021/ja00304a015) / J. Am. Chem. Soc. (1985)
  25. J. R. Miller, J. V. Beitz, R. K. Huddleston, J. Am. Chem. Soc.106, 5057 (1984). (10.1021/ja00330a004) / J. Am. Chem. Soc. (1984)
  26. S. Strauch, G. McLendon, M. McGuire, T. Guarr, J. Phys. Chem.87, 3579 (1983). (10.1021/j100242a001) / J. Phys. Chem. (1983)
  27. Preparation of the Ir(I) complex followed a published procedure ( 28 ). 2 6-Dichloro-1 4-benzoquinone (Sigma-Aldrich) was recrystallized from methanol before use. All solvents were high-purity grade; they were dried and distilled before use.
  28. J. L. Atwood et al., Inorg. Chem.23, 4050 (1984). (10.1021/ic00192a042) / Inorg. Chem. (1984)
  29. Estimated from published redox potentials of [Ir(μ-pz)(COD)] 2 ( 30 ) and 2 6-dichloro-1 4-benzoquinone ( 31 ).
  30. D. C. Smith, H. B. Gray, Coord. Chem. Rev.100, 169 (1990). (10.1016/0010-8545(90)85009-H) / Coord. Chem. Rev. (1990)
  31. S. Fukuzumi, S. Koumitsu, K. Hironaka, T. Tanaka, J. Am. Chem. Soc.109, 305 (1987). (10.1021/ja00236a003) / J. Am. Chem. Soc. (1987)
  32. B. S. Brunschwig, N. Sutin, Comments Inorg. Chem.6, 209 (1987). (10.1080/02603598708072291) / Comments Inorg. Chem. (1987)
  33. Multipole-multipole energy transfer quenching ( 34 ) of the 3 B 2 excited state of the iridium dimer will be negligible because there is no spectral overlap between [Ir(μ-pz)(COD)] 2 3 B 2 luminescence (>600 nm) and 2 6-dichloro-1 4-benzoquinone absorption (<520 nm).
  34. T. Förster, Ann. Phys. (Leipzig)2, 55 (1948). / Ann. Phys. (Leipzig) (1948)
  35. M. Inokuti, F. Hirayama, J. Chem. Phys.43, 1978 (1965). (10.1063/1.1697063) / J. Chem. Phys. (1965)
  36. A. Blumen, J. Manz, J. Chem. Phys.71, 4694 (1979). (10.1063/1.438253) / J. Chem. Phys. (1979)
  37. A. Blumen, J. Chem. Phys.72, 2632 (1980). (10.1063/1.439408) / J. Chem. Phys. (1980)
  38. 10.1021/ja000017h
  39. A. M. Napper, H. Liu, D. H. Waldeck, J. Phys. Chem. B105, 7699 (2001). (10.1021/jp0105140) / J. Phys. Chem. B (2001)
  40. The effective tunneling distance is a D-A center-to-center measure; consequently the larger *D Ir - A Q pair exhibits longer tunneling distances than *D Ru - A Fe .
  41. ET across xylyl bridges was measured with a flash-quench technique ( 42 ). Ru(bpy) 3 3+ -(xylyl) n -DMA (where n = 3 to 5) was generated in acetonitrile by quenching laser-excited Ru(bpy) 3 2+ -(xylyl) n -DMA with methylviologen. Subsequent DMA to Ru(bpy) 3 3+ ET was monitored by transient absorption spectroscopy ( 12 ). ET rates varied with the number of xyyl groups in the bridge: 9.0 × 0.3 × 10 6 s –1 n = 3; 2 τ 1 × 10 5 s –1 n = 4; 6 τ 1 × 10 3 s –1 n = 5.
  42. I.-J. Chang, H. B. Gray, J. R. Winkler, J. Am. Chem. Soc.113, 7056 (1991). (10.1021/ja00018a064) / J. Am. Chem. Soc. (1991)
  43. W. Drabowicz, Z. Naturforsch.45, 1342 (1990). (10.1515/zna-1990-11-1218) / Z. Naturforsch. (1990)
  44. W. L. Jorgensen, E. R. Laird, T. B. Nguyen, J. Tirado-Rives, J. Comp. Chem.14, 206 (1993). (10.1002/jcc.540140208) / J. Comp. Chem. (1993)
  45. 10.1126/science.290.5489.114
  46. 10.1073/pnas.081072898
  47. We thank J. Kim J. Lee and J. Magyar for several helpful discussions. Supported by BP the NSF (grant no. CHE-0078809) and the Arnold and Mabel Beckman Foundation. O.S.W. acknowledges a postdoctoral fellowship from the Swiss National Science Foundation and B.S.L. a graduate fellowship from the Parsons Foundation.
Dates
Type When
Created 20 years, 7 months ago (Jan. 6, 2005, 7:15 p.m.)
Deposited 1 year, 7 months ago (Jan. 9, 2024, 10:43 p.m.)
Indexed 1 year, 3 months ago (May 13, 2024, 4:33 a.m.)
Issued 20 years, 7 months ago (Jan. 7, 2005)
Published 20 years, 7 months ago (Jan. 7, 2005)
Published Print 20 years, 7 months ago (Jan. 7, 2005)
Funders 0

None

@article{Wenger_2005, title={Electron Tunneling Through Organic Molecules in Frozen Glasses}, volume={307}, ISSN={1095-9203}, url={http://dx.doi.org/10.1126/science.1103818}, DOI={10.1126/science.1103818}, number={5706}, journal={Science}, publisher={American Association for the Advancement of Science (AAAS)}, author={Wenger, Oliver S. and Leigh, Brian S. and Villahermosa, Randy M. and Gray, Harry B. and Winkler, Jay R.}, year={2005}, month=jan, pages={99–102} }