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Eighth CPIMS Meeting Abstract Book Program and Abstracts for CPIMS 8 Eighth Research Meeting of the Condensed Phase and Interfacial Molecular Science (CPIMS) Program Bolger Conference Center Potomac, MD October 21-24, 2012 Office of Basic Energy Sciences Chemical Sciences, Geosciences & Biosciences Division The research grants and contracts described in this document are supported by the U.S. DOE Office of Science, Office of Basic Energy Sciences, Chemical Sciences, Geosciences and Biosciences Division. i Catalytic hydrogenations are critical to many industrial processes including agricultural chemicals, foods and pharmaceuticals. Typical - Potential energy landscape of the (H2O)6 •CO2 cluster. Using heterogeneous hydrogenation catalysts involve nanoparticles supersonic expansion techniques the cluster is prepared with the composed of expensive noble metals or alloys based on platinum, excess electron localized on the water cluster. Excitation of the palladium, rhodium, and ruthenium. Small quantities of individual, asymmetric CO stretch of the CO2 or of the OH stretch of bending isolated palladium atoms can convert the otherwise catalytically inert surface of an inexpensive metal like copper into an ultraselective vibrations of a water monomer results in electron transfer to CO2 followed by loss of one or two water molecules. Direct dynamics catalyst. The mechanism involves facile dissociation of molecular hydrogen at individual palladium atom sites followed by spillover simulations show that the electron transfer process is triggered by formation of an H bond between a water molecule and the CO2. onto the copper surface, where ultraselective catalysis occurs by virtue of weak binding. The reaction selectivity is in fact much higher than Reprinted with permission from K. J. Breen, A. F.DeBlase, T. L. that measured on palladium alone, illustrating the unique synergy of Guasco, V. K. Voora, K. D. Jordan, T. Nagata, and M. A. Johnson the system. This approach is a promising strategy for designing novel “Bottom-Up View of Water Network-Mediated CO2 Reduction Using bi-functional heterogeneous catalysts in which a catalytically active Cryogenic Cluster Ion Spectroscopy and Direct Dynamics element is atomically dispersed in a more inert matrix. Moreover, Simulations”, The Journal of Physical Chemistry A, January 1, 2012. some of the best industrial alloy catalysts to date may already be Copyright 2012, American Chemical Society. operating via this mechanism, but there is currently no way to directly probe the atomic scale geometry of an alloyed nanoparticle of a Submitted by Kenneth D. Jordan (University of Pittsburgh and working catalyst. Mark A. Johnson (Yale University) G. Kyriakou, M. B. Boucher, A. D. Jewell, E. A. Lewis, T. J. Lawton, For further information, see abstract on pages 99-102. A. E. Baber, H. L. Tierney, M. Flytzani-Stephanopoulos and E. C. H. Sykes, Science, 2012, 335, 1209-1212. Submitted by E. Charles H. Sykes (Tufts University) For further information, see abstract on pages 175-178. CPIMS 8 About the Cover Graphics Influence of a dissolved ion on the structure and thermodynamics of the air‐water interface. The model anion (green), comparable in size to an iodide ion and slightly less charged, resides near the mean interfacial Nonlinear optics with surface waves. Upper panel: two height in this snapshot from a molecular simulation. Instantaneous femtosecond pulses are coupled into a gold film to form two topography of the interface (blue wire mesh, determined by coarse‐ counter-propagating surface plasmon polarition (SPP) waves. A graining the solvent’s molecular configuration) highlights, however, that silicon nanotarget is placed in the middle. Middle panel: reflection fluctuations about the average surface are substantial. image on the CCD showing the launching points of the SPP waves. Lower panel: Fourwave mixing signal (electronic coherent anti- The energy and entropy of adsorbing such a solute at the interface are Stokes Raman scattering) of the nanotarget, excited by the two both surprisingly negative, suggesting that entropy changes arise from SPP waves. Note that the particle is excited by surface waves only, the ion’s suppression of capillary‐like fluctuations. Computed energy and not by freely propagating photons. The inset shows a SEM changes, depicted in the background color pattern, originate instead from image of the Si nanoparticle. shifting populations of water molecules in surface, bulk, and solvation environments. By occupying space in the high‐energy surface region, a solute effectively reduces the contact area between liquid and vapor. The resulting decrease in surface energy can be large, but is neglected by X. Liu, Y. Wang, and E. O. Potma, "Surface-mediated four-wave traditional perspectives such as dielectric continuum theory. mixing of nanostructures with counterpropagating surface plasmon D. E. Otten, P. R. Shaffer, P. L. Geissler, and R. J. Saykally, Proceedings polaritons", Optics Letters 36, 2348-2350 (2011). of the National Academy of Science, 109, 701 (2012). Submitted by Phillip L. Geissler and Richard J. Saykally (Lawrence Berkeley National Laboratory) Submitted by Eric O. Potma (University of California, Irvine) For further information, see abstract on pages 147-149. For further information, see abstracts on pages 67-60 and pages 151-154. ii CPIMS 8 Foreword This volume summarizes the scientific content of the Eighth Research Meeting on Condensed Phase and Interfacial Molecular Science (CPIMS) sponsored by the U. S. Department of Energy (DOE), Office of Basic Energy Sciences (BES). The research meeting is held for the DOE laboratory and university principal investigators within the BES CPIMS Program to facilitate scientific interchange among the PIs and to promote a sense of program identity. During past CPIMS research meetings, investigators from other research programs have been invited to present their work. The hope is that the cross-fertilization of ideas is promoted, and the invited presentations have been well received during prior CPIMS meetings. Unfortunately, budget cuts have resulted in the need to drop temporarily the inclusion of outside speakers from the CPIMS meeting agenda. It is hoped that budget reductions can be reversed before future meetings are held. In the meantime, several CPIMS investigators have graciously agreed to present their research in the time slots freed by this decision. We are indebted to these investigators for agreeing to prepare presentations on this occasion. Reductions in budgets available for conferences have also meant that there were no hardcopies of this book printed, and that no electronic copies of the book were provided on CD-ROMs. As a consequence, the need to deliver the book in pdf format entirely by electronic means led to the extensive use of file compression. It is hoped that the resulting visual quality is acceptable to readers. We are deeply indebted to the members of the scientific community who have contributed valuable time toward the review of proposals and programs. These thorough and thoughtful reviews are central to the continued vitality of the CPIMS Program. We appreciate the privilege of serving in the management of this research program. In carrying out these tasks, we learn from the achievements and share the excitement of the research of the many sponsored scientists and students whose work is summarized in the abstracts published on the following pages. This year’s speakers are gratefully acknowledged for their investment of time and for their willingness to share their ideas with the meeting participants. Special thanks are reserved for the staff of the Oak Ridge Institute for Science and Education, in particular, Connie Lansdon and Tim Ledford. We also thank Diane Marceau, Robin Felder, and Michaelene Kyler-Leon in the Chemical Sciences, Biosciences, and Geosciences Division for their indispensable behind-the-scenes efforts in support of the CPIMS program. Finally, we thank Dawn Adin (BES/AAAS Fellow) for expert advice on the design of this pdf file. Gregory J. Fiechtner, Mark R. Pederson, and Michael P. Casassa Chemical Sciences, Geosciences and Biosciences Division Office of Basic Energy Sciences iii Agenda CPIMS 8 U. S. Department of Energy Office of Basic Energy Sciences Eighth Condensed Phase and Interfacial Molecular Science (CPIMS) Research Meeting Sunday, October 21 3:00-6:00 pm **** Registration **** 6:00 pm **** Reception (No host, Pony Express Bar & Grill) **** 7:00 pm **** Dinner (Osgood’s Restaurant) **** Monday, October 22 7:30 am **** Breakfast (Osgood’s Restaurant) **** All Presentations held in Stained Glass Hall 8:30 am Introductory Remarks Gregory J. Fiechtner, Mark R. Pederson, and Eric A. Rohlfing, DOE Basic Energy Sciences Session I Chair: Michael D. Fayer, Stanford University 9:00 am The Ultrafast Infrared Spectroscopy of Protons in Water Andrei Tokmakoff, Massachusetts Institute of Technology 9:30 am Equilibria and Dynamics at Aqueous Interfaces - SHG and SFG Studies Kenneth B. Eisenthal, Columbia University 10:00 am Correlating Electronic and Nuclear Motions during Photoinduced Charge Transfer Processes using Multidimensional Femtosecond Spectroscopies and Ultrafast X-ray Absorption Spectroscopy Munira Khalil, University of Washington 10:30 am **** Break **** Session II Chair: Gregory K. Schenter, Pacific Northwest National Laboratory 11:00 am Understanding Nanoscale Confinement Effects in Solvent-Driven Chemical Reactions Ward H. Thompson, University of Kansas 11:30 am Computational Studies of Aqueous and
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