NEW MODEL SURFACES FOR MINERAL AEROSOLS: ANILINE- LINKED OLEFINS ON SILICA STUDIED WITH BROADBAND VIBRATIONAL SFG Avram M. Buchbinder, GRACE Y. STOKES, JULIANNE M. GIBBS-DAVIS, KARL A. SCHEIDT, FRANZ M. GEIGER Northwestern University

Hayes, P. L. et al. J. Phys. Chem. C (2007) Mifflin, A. L. et al. J. Phys. Chem. B (2006) Konek, C. T. et al. J. Am. Chem. Soc. (2005) Stokes, G. Y. et al. J. Am. Chem. Soc. (2007) Boman, F. C., et al. J. Am. Chem. Soc. (2005) III Biophysics I Schmidt, C. M. et al. J. Phys. Chem. C. (2007) Schmidt, C. M. et al. Langmuir (2006) Voges, A. B., et al. J. Phys. Chem. C Feature Article (2007) Voges, A. B., et al. J. Phys. Chem. B (2004) Atmospheric Chemistry Gibbs-Davis, J. L., et al. J. Am. Chem. Soc., (2007) Konek, C. T. et al. Elsevier series on "Developments in Earth and Environmental Sciences", in press (2007) Al-Abadleh, H. A., et al. J. Phys. Chem. B (2005) Al-Abadleh, H. A., et al. J. Phys. Chem. B (2005) Al-Abadleh, H. A., et al. J. Am. Chem. Soc, (2004) Konek, C.T., et al. J. Am. Chem. Soc, (2004) Mifflin, A. L. et al. J. Phys. Chem. B (2005) Mifflin, A. L., et al. J. Phys. Chem. A (2003) Mifflin, A. L., et al. J. Phys. Chem. A (2003) II Geochemistry

Hayes, P. L. et al. J. Phys. Chem. C (2007) Mifflin, A. L. et al. J. Phys. Chem. B (2006) Konek, C. T. et al. J. Am. Chem. Soc. (2005) Stokes, G. Y. et al. J. Am. Chem. Soc. (2007) Boman, F. C., et al. J. Am. Chem. Soc. (2005) III Biophysics I Schmidt, C. M. et al. J. Phys. Chem. C. (2007) Schmidt, C. M. et al. Langmuir (2006) Voges, A. B., et al. J. Phys. Chem. C Feature Article (2007) Voges, A. B., et al. J. Phys. Chem. B (2004) Atmospheric Chemistry Gibbs-Davis, J. L., et al. J. Am. Chem. Soc., (2007) Konek, C. T. et al. Elsevier series on "Developments in Earth and Environmental Sciences", in press (2007) Al-Abadleh, H. A., et al. J. Phys. Chem. B (2005) Al-Abadleh, H. A., et al. J. Phys. Chem. B (2005) Al-Abadleh, H. A., et al. J. Am. Chem. Soc, (2004) Konek, C.T., et al. J. Am. Chem. Soc, (2004) Mifflin, A. L. et al. J. Phys. Chem. B (2005) Mifflin, A. L., et al. J. Phys. Chem. A (2003) Mifflin, A. L., et al. J. Phys. Chem. A (2003) II Geochemistry

Terpenes

Terpenes Biogenic VOC sources outweigh anthropogenic sources 5:1 Finlayson-Pitts, B. J.; Pitts, J. N. Chemisry of the Upper and Lower Atmosphere; Academic Press: New York, 1999.

Terpenes Limonene Biogenic VOC sources outweigh anthropogenic sources 5:1 Finlayson-Pitts, B. J.; Pitts, J. N. Chemisry of the Upper and Lower Atmosphere; Academic Press: New York, 1999.

Terpenes homogeneous oxidation O 3 partially oxidized VOCs Limonene Ellison, B.G.; Tuck, A.F.; Vaida, V. J.; J. Geophys. Res. 1999, 104, Murphy, D. M.; Thompson, D. S.; Mahoney M. J.; Science, 1998, 282, 1664 Atkinson, R.; Arey, J. Chem. Rev. 2003, 103, 4605.

Terpenes homogeneous oxidation O 3 partially oxidized VOCs Limonene Ellison, B.G.; Tuck, A.F.; Vaida, V. J.; J. Geophys. Res. 1999, 104, Murphy, D. M.; Thompson, D. S.; Mahoney M. J.; Science, 1998, 282, 1664 Atkinson, R.; Arey, J. Chem. Rev. 2003, 103, O3O3

Terpenes homogeneous oxidation O 3 partially oxidized VOCs Limonene O3O3 Ellison, B.G.; Tuck, A.F.; Vaida, V. J.; J. Geophys. Res. 1999, 104, Murphy, D. M.; Thompson, D. S.; Mahoney M. J.; Science, 1998, 282, 1664 Atkinson, R.; Arey, J. Chem. Rev. 2003, 103, 4605.

Ellison, B.G.; Tuck, A.F.; Vaida, V. J.; J. Geophys. Res. 1999, 104, Murphy, D. M.; Thompson, D. S.; Mahoney M. J.; Science, 1998, 282, 1664 Atkinson, R.; Arey, J. Chem. Rev. 2003, 103, IPCC, 2007: Summary for Policymakers. In Climate Change 2007: The Physical science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change; Solomon, S., et al. Eds.; Cambridge University Press: New York, Terpenes Hydrophilic oxidized organic adlayer mediates cloud nucleation with consequences for radiative forcing “Aerosols… remain the dominant uncertainty in radiative forcing” Climate Change 2007 IPCC

Ellison, B.G.; Tuck, A.F.; Vaida, V. J.; J. Geophys. Res. 1999, 104, Murphy, D. M.; Thompson, D. S.; Mahoney M. J.; Science, 1998, 282, 1664 Atkinson, R.; Arey, J. Chem. Rev. 2003, 103, IPCC, 2007: Summary for Policymakers. In Climate Change 2007: The Physical science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change; Solomon, S., et al. Eds.; Cambridge University Press: New York, Terpenes Hydrophilic oxidized organic adlayer mediates cloud nucleation with consequences for radiative forcing “Aerosols… remain the dominant uncertainty in radiative forcing” Climate Change 2007 IPCC How fast?

Ellison, B.G.; Tuck, A.F.; Vaida, V. J.; J. Geophys. Res. 1999, 104, Murphy, D. M.; Thompson, D. S.; Mahoney M. J.; Science, 1998, 282, 1664 Atkinson, R.; Arey, J. Chem. Rev. 2003, 103, IPCC, 2007: Summary for Policymakers. In Climate Change 2007: The Physical science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change; Solomon, S., et al. Eds.; Cambridge University Press: New York, Terpenes Hydrophilic oxidized organic adlayer mediates cloud nucleation with consequences for radiative forcing “Aerosols… remain the dominant uncertainty in radiative forcing” Climate Change 2007 IPCC How fast? How does molecular orientation, structure and variability control reactivity?

Terpenes Hydrophilic oxidized organic adlayer mediates cloud nucleation with consequences for radiative forcing “Aerosols… remain the dominant uncertainty in radiative forcing” Climate Change 2007 IPCC How fast? How does molecular orientation, structure and variability control reactivity? How can we address the complexity of the system? Ellison, B.G.; Tuck, A.F.; Vaida, V. J.; J. Geophys. Res. 1999, 104, Murphy, D. M.; Thompson, D. S.; Mahoney M. J.; Science, 1998, 282, 1664 Atkinson, R.; Arey, J. Chem. Rev. 2003, 103, IPCC, 2007: Summary for Policymakers. In Climate Change 2007: The Physical science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change; Solomon, S., et al. Eds.; Cambridge University Press: New York, 2007.

Previous models undec-10-ene-1-thiol SAM on gold Fiegland, L. R.; McCorn Saint Fleur, M.; Morris, J. R. Langmuir 2005, 21, octenyltrichlorosilane, allyltrichlorosilane on silicon Dubowski, Y.; Vieceli, J.; Tobias, D. J.; Gomez, A.; Lin, A.; Nizkorodov, S. A.; McIntire, T. M.; Finlayson- Pitts, B. J. JPC A 2004, 108, Oleic acid coating Moise, T.; Rudich, Y. JPC A 2002, 106, Hearn, J. D.; Lovett, A. J.; Smith, G. D. PCCP 2005, 7, 501. Oleic Acid Languir-Blodgett film Voss, L.F.; Bazerbashi, M. F.; Beekman, C. P.; Hadad, C. M.; Allen, H. C. J. Geophys. Res. 2007, 112, D06209 Voss, L. F.; Hadad, C. M.; Allen, H. C. J. Phys. Chem. B. 2006, 110, Previous studies mainly straight-chain unsaturated systems High variability of reaction probability for terpenes in the gas phase; but chemical variability has not been addressed for heterogeneous reactions. 10-undecenoic acid Langmuir-Blodgett film Elisason, T. L.; Aloisio, A.; Donaldson, D. J.; Cziczo, D. J.; Vaida, V. Atmos. Env. 2003, 37, 2207.

Diversity-oriented surface functionalization strategies electrophilic/nucleophilic Address chemical diversity and complexity – study any organic moiety at will Covalently couple analyte to surface to avoid volatilization Use a standardized “linker” approach to allow for synthetic versatility Zhang, F.; Srinivasan, M. P. Langmuir, 2004, 20, 2309 Voges, A. B.; Al-Abadleh, H. A.; Musorrafiti, M. J.; Bertin, P. A.; Nguyen, S. T.; Geiger, F. M. J. Phys. Chem. B 2004, 108, Voges, A. B.; Stokes, G. Y.; Gibbs-Davis, J. M.; Lettan, R. B., II; Bertin, P. A.; Pike, R. C.; Nguyen, S. T.; Scheidt, K. A.; Geiger, F. M. J. Phys. Chem. C. (Feature Article); 2007, 111, 1567.

Aliphatic Linkers Spectra can be congested due to aliphatic linker vibrational modes Voges, A. B.; Al-Abadleh, H. A.; Musorrafiti, M. J.; Bertin, P. A.; Nguyen, S. T.; Geiger, F. M. J. Phys. Chem. B 2004, 108, Voges, A. B.; Stokes, G. Y.; Gibbs-Davis, J. M.; Lettan, R. B., II; Bertin, P. A.; Pike, R. C.; Nguyen, S. T.; Scheidt, K. A.; Geiger, F. M. J. Phys. Chem. C. (Feature Article); 2007, 111, 1567.

Linker is spectrally silent in the aliphatic C-H region Aromatic linker is more rigid than aliphatic linker pi-bonding promotes well packed surface Aromatic Linkers

Broadband Vibrational SFG ω 2 3 μm ω nm ω 3 = ω 1 + ω 2 ωω

Aromatic linker Insignificant signal below 3000 cm -1 Peak above 3000 cm -1 in phenyl silane is due to para- H which does not cancel by symmetry Broadband SFG Spectra

Tailor-made organic surfaces for addressing chemical complexity and chemical diversity

Taylor-made surface functionalization for: Atmospheric chemistry Biochemical sensing Geochemistry Catalysis Molecular electronics

Aniline-linked Limonene SSP

Aniline-linked Limonene SSP

Peak Assigment Strategy: Use molecules with similar structural motifs to isolate spectral features

Aniline-linked Limonene SSP Yang, M.; Somorjai, G. A. J. Phys. Chem. B. 2004, 108, Lu, R.; Gan, W.; Wu, B.; Chen, H. Wang, H. F. J. Phys. Chem. B. 2004, 108, Yang, M.; Chou, K. C.; Somorjai, G. A. J. Phys. Chem. B. 2003, 107, Lu, R.; Gan, W.; Wu, B.; Zhang, Z.; Guo, Y.; Wang, H. F. J. Phys. Chem. B. 2005, 109, Fiegland, L. R.; McCorn Saint Fleur, M.; Morris, J. R. Langmuir 2005, 21, Voges, A. B.; Stokes, G. Y.; Gibbs-Davis, J. M.; Lettan, R. B., II; Bertin, P. A.; Pike, R. C.; Nguyen, S. T.; Scheidt, K. A.; Geiger, F. M. J. Phys. Chem. C. (Feature Article); 2007, 111, 1567.

SSP CH 2 ss CH 2 fr CH 3 as =CH CH 3 ss Aniline-linked Limonene Yang, M.; Somorjai, G. A. J. Phys. Chem. B. 2004, 108, Lu, R.; Gan, W.; Wu, B.; Chen, H. Wang, H. F. J. Phys. Chem. B. 2004, 108, Yang, M.; Chou, K. C.; Somorjai, G. A. J. Phys. Chem. B. 2003, 107, Lu, R.; Gan, W.; Wu, B.; Zhang, Z.; Guo, Y.; Wang, H. F. J. Phys. Chem. B. 2005, 109, Fiegland, L. R.; McCorn Saint Fleur, M.; Morris, J. R. Langmuir 2005, 21, Voges, A. B.; Stokes, G. Y.; Gibbs-Davis, J. M.; Lettan, R. B., II; Bertin, P. A.; Pike, R. C.; Nguyen, S. T.; Scheidt, K. A.; Geiger, F. M. J. Phys. Chem. C. (Feature Article); 2007, 111, 1567.

Reaction with Ozone Reaction probability γ (fraction of collisions resulting in reaction) Gas Phase γ = 5 x Heterogeneous reaction higher probabilty by x Dubowski, Y.; Vieceli, J.; T., D. J.; Gomez, A.; Lin, A.; Nizkorodov, S. A.; Mc.Inritre, T. M.; Finlayson-Pitts, B. J. J. Phys. Chem. A 2004, 108, Voges, A. B.; Stokes, G. Y.; Gibbs-Davis, J. M.; Lettan, R. B., II; Bertin, P. A.; Pike, R. C.; Nguyen, S. T.; Scheidt, K. A.; Geiger, F. M. J. Phys. Chem. C. (Feature Article); 2007, 111, 1567.

Reaction with Ozone Reaction probability γ (fraction of collisions resulting in reaction) Dubowski, Y.; Vieceli, J.; T., D. J.; Gomez, A.; Lin, A.; Nizkorodov, S. A.; Mc.Inritre, T. M.; Finlayson-Pitts, B. J. J. Phys. Chem. A 2004, 108, Voges, A. B.; Stokes, G. Y.; Gibbs-Davis, J. M.; Lettan, R. B., II; Bertin, P. A.; Pike, R. C.; Nguyen, S. T.; Scheidt, K. A.; Geiger, F. M. J. Phys. Chem. C. (Feature Article); 2007, 111, 1567.

Amide -linked terpene + 30 ppm ozone CH 3 as signal decreases as it changes orientation during reaction  E SFG [a.u.] CH 3 as 2961 cm Time [min] Voges, A. B.; Stokes, G. Y.; Gibbs-Davis, J. M.; Lettan, R. B., II; Bertin, P. A.; Pike, R. C.; Nguyen, S. T.; Scheidt, K. A.; Geiger, F. M. J. Phys. Chem. C. (Feature Article); 2007, 111, Assume first order kinetics Initial reaction probability γ = 10 -5

Determine how accessibility and orientation govern reactivity for various terpenes Gas Phase ReactionSurface Reaction Future work – Accessibility

Chiral Atmospheric Surface Chemistry? H O H H O H In gas phase ozone can collide from any direction, so the reaction is not diasteriomerically specific. On a surface ozone can only collide from the top and the reaction may be diasteriomerically specific for bound molecules. This specificity will also depend on surface residence time. H O H H O H

Silane linker chemistry facilitates study of taylor-made organic adlayers Spectrally silent aromatic linkers are useful tool for surface spectroscopy Reaction probability of for heterogeneous reaction of terpenes with ozone is greatly enhanced over gas phase reaction Heterogeneous reactions of terpenes in the atmosphere must be considered in order to accurately predict climate Conclusions

Silane linker chemistry facilitates study of taylor-made organic adlayers Spectrally silent aromatic linkers are useful tool for surface spectroscopy Reaction probability of for heterogeneous reaction of terpenes with ozone is greatly enhanced over gas phase reaction Heterogeneous reactions of terpenes in the atmosphere must be considered in order to accurately predict climate Conclusions

Silane linker chemistry facilitates study of taylor-made organic adlayers Spectrally silent aromatic linkers are useful tool for surface spectroscopy Reaction probability of for heterogeneous reaction of terpenes with ozone is greatly enhanced over gas phase reaction Heterogeneous reactions of terpenes in the atmosphere must be considered in order to accurately predict climate Conclusions

Silane linker chemistry facilitates study of taylor-made organic adlayers Spectrally silent aromatic linkers are useful tool for surface spectroscopy Reaction probability of for heterogeneous reaction of terpenes with ozone is greatly enhanced over gas phase reaction Variability in heterogeneous reactions of terpenes in the atmosphere must be considered to predict climate Conclusions

Acknowledgements Prof. Franz Geiger Prof. Karl Scheidt Grace Stokes Dr. Julianne Gibbs-Davis Dr. Andrea Voges Funding: NASA Earth and Space Sciences Predoctoral Fellowship (GYS) NASA Earth Systems Sciences Predoctoral Fellowship (ABV) Camille & Henry Dreyfus Postdoctoral Fellowship in Environmental Chem. (JGD) Sloan Fellowship (FMG) NSF EAR Atmospheric Sciences Program DOE BES Geochemistry Program Northwestern University International Institute for Nanotechnology Northwestern University Institute for Catalysis and Energy Processes

Future work – Orientation Analysis CH 3 as CH 3 ss Null polarization measurements

Aliphatic Linkers SPSSSP Voges, et al. J. Phys. Chem. C. 2007, 111,

CH 3 as CH 2 fr CH 2 ss CH 2 fr CH 3 as CH 2 ss (ring) CH 2 ss (linker) Aliphatic Linkers

Future work – Ozone Reactions Mechanism Determination for Heterogeneous Reaciton Track gas phase products Track changes in orientation Track surface reaction in C-O stretching region

Peak Assigment Strategy: Use molecules with similar structural motifs to isolate spectral features

Aromatic Linkers

Broadband Vibrational SFG ω 2 3 μm ω

Broadband Vibrational SFG ω 2 3 μm ω nm ω

Broadband Vibrational SFG ω 2 3 μm ω nm ω 3 = ω 1 + ω 2 ωω