Issue Number 35

-Surfa s c a e AS URFACE EWS G G –S N

News November 2002

Editors Note GSDList and Web Site Recently we have retired the computer which used to run our This issue of the News- mailing list. With the new computer (it is actually a 5 year old letter is also available box) came also a new software into play. As you may have on the Web site noted we are still not that experienced with it. Hence, some messages were delayed. What happens is, that if you post a http://www.phchem.uni- message from an adress which is not the address under essen.de/gsd/ which you are subscribing, the message is held for approval. You will need the That prevents abuse by spammers. In some cases we have Adobe Acrobat Reader not recognized this situation fast enough. A new feature is (which is a free down- that we have an archive of old posting online. Look for a link load from the Adobe on our website. Web site ) or a compat- ible viewer. Gas-Surface Dynamics Email Server - availa- ble to all those on the Gas-Surface News Mailing list. Just send your message to [email protected] essen.de.

Next Issue- Copy due in February 2003. Please get in touch if you wish to contribute in any way.

INSIDE THIS ISSUE 2 Research Report - Gas-Surface Dynamics and Electronic Degrees of Freedom in Essen

5 Papers for Publication 8 Job Vacancies and Announcements 16 Diary Page

Editor - Isabel Nieto. University of Essen, Fachbereich Chemie, D-45117 Essen, Germany. Tel: +49 (0)201 1833056; FAX: +49 (0)201 1833228. Email: [email protected]. Web page containing announcements and other information: http:// www.pchem.uni-essen.de/gsd/ Gas-Surface News

Research Report Gas-Surface Dynamics and Electronic Degrees of Freedom in Essen Eckart Hasselbrink, Hermann Nienhaus and Andreas Wucher Fachbereiche Chemie und Physik, Universität Essen, D-45117 Essen, Germany Starting October 2002 the German research council (DFG) has granted a collaborative research effort — a so- called Sonderforschungsbereich — to the Universität Essen. The common theme is energy dissipation at surfaces. Not only Essen researchers are involved in this consortium, but also research groups from Bochum, Duisburg and Jülich. Presently 14 projects are funded. Their subjects stretch from electro-migration, over the elementary friction in a point contact and the energy dissipation in ablation processes using femtosecond lasers to the interaction of plasma source beam with walls. Also two theoretically oriented projects are part of the research effort. In the context of gas-surface dynamics three groups are of particular interest. In the following we want to illustrate our research. Molecular beam scattering ling such that no large separation would result before the energy is dissipated.2 The Hasselbrink group uses molecular beams and laser spectroscopy to study gas-surface interaction Devoted to an alternative interpretation of the dynamics. A recent example is the work on the dis- Burne experiment the group designed an experi- ment to look for O-atoms in the gas phase (Þg. 1), sociation dynamics of O2 on Al(111). which would result from an abstraction reaction in Since the seminal experiments by Brune et al.1 the which one of the atoms is adsorbed on the surface dynamics of the adsorption of O on Al(111) has 2 and the other expelled into the gas phase. The O / been a hot topic in the gas-surface dynamics com- 2 Al(111) system is unique in so far as the thermody- munity. Using a STM they had observed features namics allow for such an reaction to occur. indicating that isolated single atoms are adsorbed on the surface and not pairs as one would have Indeed O-atoms are found in the gas phase using 2+1-photon REMPI for detection (Þg. 2). The data expected and has been later demonstrated for O2/ Pt(111). The original interpretation — that the large shows a strong increase of the yield with transla- excess energy from dissociative chemisorption tional energy of the incident molecules. As a nice allows the two fragment atoms to separate over a coincidence Andrew Kummel’s group in San Diego distance larger than 80 Å — has been questioned started at the same time to study this system using a soon after, since model calculations indicated that molecular beam for dosing and an STM for surface the corrugation of the surface would frequently analysis. This effort not only conÞrmed the Brune change the direction in which each atom is travel- experiment but also demonstrated that a higher translational energies also pairs of adatoms are

Prism Lens Laser 1 9 beam 8 7 6 5

4 Electrostatic ° 90 Deflector (300V) 3 O-atoms lenses

2

Sample ToF tube (-160 V) 0.1 9 8 Laser -2100 V MCP 7 focus O-ions -100 V 6 Anode 5 Molecular beam 4

Oxygen Atom Yield [counts/pulse] 3 Signal 0 50 100 150 200 250 300 Prism Laser O2 Translational Energy [meV] beam

Fig. 1: Experimental set-up for the detection of O-atoms Fig. 2: Yield of oxygen atoms in the gas phase per incom- resulting from an abstraction reaction. ing molecule as function of incident translational energy.

2 Gas-Surface News

O2 energies less than the metal work function and the process of energy dissipation has remained specula- r () θ tive for a long time. Our experimental approach by vO2 r O vO() using solid state barrier devices like Schottky z diodes has made direct measurement of reaction- induced hot electrons and holes at metal surfaces - r e- e feasible. In case of Schottky contacts, metal Þlms in the nm range are evaporated onto semiconductor substrates and the chemical reaction occurs at the Al surface of the thin Þlm. As illustrated in Þgure 4, chemically created hot electrons may travel ballisti- Fig. 3: cartoon illustrating the rapid transfer of two elec- cally from the surface toward the interface and trons to the incoming oxygen molecule which then traverse the Schottky barrier if their energy exceeds undergoes an abstraction reaction, where one of the atoms the barrier height Φ. CBM and VBM denote the con- is expelled. duction band minimum and valence band maxi- mum of the semiconductor, respectively. The

3 electrons are then detected as a chemicurrent in the observed with increasing abundance. However, we diode. The current transients with gas exposure do not want to sweep under the rug, that this inter- time reßect the kinetics of the respective surface pretation of the STM images is still disputed in par- reaction. ticular with Peter Varga’s group in Vienna.4 Recent studies of chemicurrents induced by various From these experiments the following picture gas/metal reactions demonstrate that the non-adia- evolves. Charge transfer to the incoming molecule batic energy dissipation is a general phenomenon5,6. is favoured in the upright geometry. For dissocia- Currents were detected with exothermic reactions tion the transfer of a second electron is necessary. In of gases like O2, O, H, D, NO, NO2, H2O with Ag, this event an unstable situation arises, since the sec- Cu, Au, Pd, Mg, Ge and Fe surfaces. This effect may ond O-atom is too far away from the surface to be be applied for sensitive gas detection and for stud- captured. Hence, it is expelled into the gas phase. ies of the kinetic parameters like cross sections of However, the charge remains on the surface. the gas/surface reaction. This interpretation is an interesting challenge to the theory community, since it is at odds with the Energetic particle surface collisions results from recent calculations using density func- The Applied Surface Science Group (Professor tional theory. It also pours new oil into the ever last- Andreas Wucher) investigates particle solid interac- ing debate over adiabaticity versus non-adabaticity in chemisorption events.

Detection of surface electronic excitations The group of Hermann Nienhaus has recently moved from Duisburg to Essen (~20km). Their activities focus on a novel experiment to detect the long speculated about creation of electron-hole pairs in exothermic adsorption and dissociative chemisorption events. The dissipation of chemical energy during exother- mic surface reactions at metals may happen adia- batically by creation of phonons or non- adiabatically by excitation of electron-hole pairs in the metal surface. The latter has been discussed in many theoretical models, however, direct experi- mental evidence was available only for very exo- thermic systems where exoemission of electrons could be detected. Most surface reactions release Fig. 4: Principle of chemicurrent detection with an ultrathin metal/n-semiconductor (Schottky) contact.

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Gas-Surface News

tion processes that occur when energetic gas phase probability of a sputtered particle as well as its particles hit a solid surface. In most cases, the dependence on the surface chemistry (“matrix kinetic energy range is chosen such that the primary effect”), a fact that opens the door towards quantita- energy dissipation channel is by elastic or inelastic tive information about the yields of sputtered parti- collisions occurring either between projectile and cles. In particular, the employed method is ideally surface atoms on one hand or among surface atoms suited for soft, but extremely efÞcient ionization of on the other hand. One of the major outcome of molecular species without signiÞcant fragmenta- such a collision cascade is the removal of surface tion. It is therefore employed to tackle one of the atoms or molecules into the gas phase (sputtering). fundamental open questions in sputtering physics The fundamental mechanisms behind the sputter- which is related to the formation processes of com- ing process, which is of great importance in many plex molecules and clusters detected in the sput- technological applications, are investigated using tered ßux which can be composed of more than mass spectrometric methods detecting the sputtered hundred surface atoms (Þg 5). Detailed knowledge particles. One of the group’s strengths is the detec- in this area is of great importance since mass spec- tion of neutral atomic and molecular species using trometry of such species can give molecular infor- laser based single photon ionization schemes in mation about the surface structure in the uppermost combination with time-of-ßight mass spectrometry. atomic layers of a solid. As another currently “hot” This technique is somewhat complementary to the topic in this Þeld, the use of polyatomic projectile well established SIMS method (Secondary Ion Mass species in order to enhance the sputtering of such Spectrometry), where the ionic species leaving the complex molecular species while minimizing their surface are detected. Using both methods simulta- collision induced fragmentation is explored. neously, it is possible to determine the ionization For all three groups the new collaborative funding scheme opens new opportunities for research. At the same time there are ample opportunities for pro- spective graduate students and post-docs. Positions for qualiÞed candidats are available at each level. Please contact us at the address given above. 1 H. Brune, J. Wintterlin, J. Trost, G. Ertl, J. Wiech- ers and R.J. Behm, J. Chem. Phys. 99, 2128 (1993). 2 G. Wahnström, A.B. Lee and J. Strömquist, J. Chem. Phys 105, 326 (1996) 3 A.J. Komrowski, J.Z. Sexton, A.C. Kummel, M. Binetti, O. Weiße and E. Hasselbrink, Phys. Rev. Lett. 87, 246103 (2001). 4 M. Schmidt, G. Leonardelli, R. Tscheließnig, A. Biedermann and P. Varga, Surf. Sci. 78, L355 (2001). Fig. 5: Mass spectrum of Indium atoms and clusters 5 H. Nienhaus, Surf. Sci. Rep. 45, 1(2002). sputtered from a polycrystalline Indium surface by 6 B. Gergen, H. Nienhaus, E. W. McFarland, W. H. 15keV Xe+ ions. Weinberg, Science 294, 2521 (2001).

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Papers for Publication Hellsing, H. S. Dominigos, P. D. Bristow, Surf. Sci., in press ¥ “Adsorption of He atoms in external grooves of ¥ “Charge transfer and re-bonding effects at doped single wall carbon nanotube bundles,” A. Siber, alpha and delta-phases of Bi O ,” H. S. Domin- Phys. Rev. B, accepted 2 3 gos, P. D. Bristowe, J. Carlsson, B. Hellsing, ¥ “Stable C-atom displacements on HOPG surface Comp. Mater. Sci., in press under plasma low-energy argon-ion bombard- ¥ “Anomalous charge-transfer behavior in the scat- ment,” B. Rousseau, H. Estrade-Szwarckopf, A.- tering of hyperthermal Br+(3P ) on Pt(111),” M. L. Thomann, P. Brault, Appl. Phys. A, accepted 2 Maazouz, P. L. Maazouz, D. C. Jacobs, J. Chem. ¥ “Surface reactivity of highly vibrationally excited Phys., in press

molecules prepared by pulsed laser excitation: + ν ¥ “Reaction of 5eV O with a decanethiolate/ CH4 (2 3) on Ni(100),” M. P. Schmid, P. Maroni, R. D. Beck, T. R. Rizzo, J. Chem. Phys., Au(111) self-assembled monolayer,” X. Quin, T. accepted Tzvetkov, D. C. Jacobs, Nucl. Instrum. Meth.B, in press ¥ “Kinetic Monte Carlo simulations of the auto-cat- alytic adsorption effect: CO on ZnO,” J. Stephan, •“Trajectory-dependent energy- and charge-trans- +(3P ) on Pt(111),” P. L. Maa- U. Burghaus, JVSTA (AVS-2002), submitted fer in collisions of Br 2 zouz, M. Maazouz, D. C. Jacobs, Nucl. Instrum. ¥ “Coadsorption of CO and hydrogen on the Zn- Meth. B, in press terminated surface of ZnO: A molecular beam ¥ “Dynamical study of ion beam oxidation: incorpo- study,” M. Kunat, U. Burghaus, JVSTA (AVS- ration of hyperthermal oxygen ions into silicon 2002), submitted oxide thin films,” T. Tzvetkov, X. Qin, D. C. ¥ “Photochemistry of molecules caged in amor- Jacobs, Phys. Rev. B, submitted phous solid water: A model for hydrocarbons for- ¥ “Adsorption kinetics of CO on Cr/Ru surfaces,” R. mation in interstellar spaces,” Y. Lilach, M. Denecke, B. Tränkenschuh, M. P. Engelhardt, H.- Asscher P. Steinrück, Surf. Sci., in press ¥ “Surface processes induced by collisions,” M. ¥ “Kinetic parameters of CO adsorbed on Pt(111) Asscher, Y. Zeiri studied by in-situ high resolution X-ray pho-

¥ “Angular distribution of H2 molecules scattered toemission,” M. Kinne, T. Fuhrmann, C. M. Whe- from the Pd(111) surface,” C. Díaz, H. F. Bus- lan, J. F. Zhu, J. Pantförder, M. Probst, G. Held, nengo, F. Martín, A. Salin, J. Chem. Phys., R. Denecke, H. - P. Steinrück, J. Chem. Phys., in accepted press ¥ “Model study of adsorbed metallic quantum dots: ¥ “In-situ high resolution XPS studies on adsorp- Na on Cu(111),T. Torsti, V. Lindberg, M. J. Puska, tion of NO on Pt(111) surfaces,” J. F. Zhu, M. B. Hellsing, Phys. Rev. B, in press Kinne, T. Fuhrmann, R. Denecke, H.-P. Stein- rück, Surf. Sci., submitted ¥ “Charge accumulation and barrier formation at grain boundaries in ZnO decorated with Bi,“ H. S. ¥ “CO vibrational frequencies on methanol synthe- Domingos, J. M. Carlsson, P. D. Bristowe, B. sis catalysts: a DFT study,” J. Greeley, A. Hellsing, J. Phys.: Cond. Matt., in press Gokhale, J. Kreiser, H. Tops¿e, N.-Y. Tops¿e, J. A. Dumesic, M. Mavrikakis, J. Cat., in press ¥ “Lifetime of holes and electrons at metal sur- faces; electron-phonon coupling,” B. Hellsing, A. •“Pentacene ultrathin film formation on reduced Eiguren, F. Reinert, G. Nicolay, E. V. Chulkov, V. and oxidized Si surfaces,” R. Ruiz, B. Nickel, N. M. Silkin, S. Hufner, P. M. Echenique, E. V. Koch, L. C. Feldmann, R. F. Haglund, A. Kahn, Chulkov, J. Electr. Spectr. Rel. Phen., in press G. Scoles, submitted ¥ “Effect of doping a grain boundary in ZnO with ¥ “Structural investigation of monolayers prepared various concentrations of Bi,” J. M. Carlsson, B. by deposition of (CH3S)2 on the (111) face of sin-

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gle-crystal gold,” M. F. Danisman, L. Casalis, G. Benesch, M. Hagedorn, H. Merz, H. Zacharias, Bracco, G. Scoles, J. Phys. Chem., accepted Phys. Rev. B., in press ¥ “Using nanografting to achieve directed assem- ¥ “Resonance in the 1π photoemission cross-sec- bly of de novo designed metalloproteins on gold,” tion of CO on Pt(111) measured by High Har- M. A. Case, G. L. McLendon, Y. Hu, T. K. Vander- monic radiation,” G. Tsilimis, J. Kutzner, H. lick, G. Scoles, Nanoletters, accepted Zacharias, Surf. Sci., in press ¥ “Hyperthermal molecular beam deposition of ¥ “The transition from amorphous silicon oxide to highly ordered organic thin films,” L. Casalis, M. crystalline silicon studied by photoelectron dif- F. Danisman, B. Nickel, G. Bracco, T. Toccoli, S. fraction,” C. Westphal, S. Dreiner, M. Schür- Iannotta, G. Scoles, submitted mann, H. Zacharias, Surf. Rev. Lett., in press ¥ “Abstraction of D chemisorbed on graphite ¥ “Angle-scanned photoelectron diffraction on (0001) with gaseous H atoms,” T. Zecho, A. clean and hydrogen terminated (2x1) recon- Guettler, X. Sha, D. Lemoine, B. Jackson, J. structed Si(100) surfaces,” S. Dreiner, C. West- Kueppers, Chem. Phys. Lett., accepted phal, M. Schürmann, H. Zacharias, Thin Solid Films ¥ “Efficient Eley-Rideal reactions of H atoms with single C1 adsorbates on Au(111),” D. Lemoine, J. ¥ “Optical high excitation of diamond: Phase dia- G. Quattrucci, B. Jackson, Phys. Rev. Lett., sub- gram of excitons, electron-hole liquid and elec- mitted tron-hole plasma,” N. Teofilov, R. Schliesing, K. Thonke, H. Zacharias, R. Sauer, H. Kanda, Dia- ¥ “Eley-Rideal reactions of H atoms with C1 mond Rel. Mater. adsorbed on Au(111): quantum and quasiclassi- cal studies,” J. G. Quattrucci, B. Jackson, D. ¥ “Small molecules condensed on surfaces: A Lemoine, J. Chem. Phys., accepted study of N2O on NaCl(100),” B. Redlich, L. van der Meer, H. Zacharias, G. Meijer, G. von •“Variational transform method and the split oper- Helden, Nucl. Instrum. Meth. A ator propagator,” D. Lemoine, J. Chem. Phys., submitted ¥ “Adsorption of O2 on Si(111)-7x7 at 300K and 30K studied by ion photodesorption and electron ¥ “A density functional theory study of enantiospe- photoemission,” G. Comtet, L. Hellner, G. Dujar- cific adsorption at chiral surfaces,” Z. Slijivan- din, K. Bobrov, Phys. Rev. B canin, K. V. Gothelf, B. Hammer, J. Am. Chem. Soc., in press ¥ “Thermal and adsorbate induced plasmon energy shifts in graphite,” M. Gleeson, B. ¥ “A simple and realistic model system for studying Kasemo, D. Chakarov, Surf. Sci., accepted hydrogen bonds in β-sheets,” J. Rossmeisl, B. Hinnemann, K. W. Jacobsen, J. K. N¿rskov, O. H. ¥ “Crystallization kinetics of thin amorphous water Olsen, J. T. Pedersen, submitted films on surfaces,” P. Löfgren, P. Ahlstrom, J. Lausmaa, B. Kasemo, D. Chakarov, Langmuir, ¥ “Atomic and electronic structure of MoS2 nano- accepted particles,” M. V. Bollinger, K. W. Jacobsen, J. K. N¿rskov, submitted ¥ “Phonons and specific heat of linear dense phases of atoms physisorbed in the grooves of ¥ “Conductance calculations with a wavelet basis carbon nanotube bundles,” A. Siber, Phys. Rev. set,” K. S. Thygesen, M. V. Bollinger, K. W. B., accepted Jacobsen, submitted ¥ “Surface strain versus substrate interaction in ¥ “Adsorption of small palladium clusters on the heteroepitaxial metal layers: Pt on Ru(001),” A. relaxed Al2O3(0001) surface, J. R. B. Gomes, Z. Schlapka, M. Lischka, A. Gro§, P. Jakob, submit- Lodziana, J. Illas, submitted ted ¥ “Unoccupied surface states of the c(2x2) - recon- ¥ “Dynamics of molecule-surface interactions from structed 3C - SiC(001) surface,” R. Ostendorf, C. first principles,” review paper, submitted

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Gas-Surface News

¥ “Unified picture of the molecular adsorption pro- Minton, S. J. Sibener, Prog. Org. Coatings, cess: O2/Pt(111),” A. Gro§, A. Eichler, J. Hafner, accepted M. J. Mehl, D. A. Papaconstantopoulos, Phys. Rev. Lett., submitted ¥ “Incidence angle dependence of scattering and dissociation of O2 on Al(111): Possible weakly ¥ “Dissociative adsorption of hydrogen on strained bound molecular precursors,” O. Wei§e, C. Cu surfaces,” S. Sakong, A. Gro§, Surf. Sci., Wesenberg, M. Binetti, E. Hasselbrink, C. Cor- accepted riol, G. R. Darling, S. Holloway, J. Chem. Phys., submitted ¥ “Surface photochemistry induced by ultrafast pulses of vacuum ultraviolet light: O2/graphite,” D. ¥ “An AFM study of the growth kinetics of the self- Riedel, L. M. A. Perdigão, J. L. Hernández- assembled octadecylsiloxane monolayer on oxi- Pozos, Q. Guo, R. E. Palmer, J. S. Foord, K. W. dized silicon,” T. Balgar, R. Bautista, N. Hart- Kolasinski, Phys. Rev. B, in press mann, E. Hasselbrink, Surf. Sci., in press ¥ “The structure of water on the (0001) surface of ¥ “The role of non-adiabatic pathways and molecu- graphite,” P. Cabrera Sanfelix, S. Holloway, K. W. lar rotations in the oxygen abstraction reaction Kolasinski, G. R. Darling, Surf. Sci., accepted on the Al(111) surface”, M. Binetti, O. Wei§e, E- Hasselbrink, G. Katz, R. Kosloff, Y. Zeiri, Phys. ¥ “Changes in surface phonon dispersion,” M. Rev. Lett., submitted Rocca, Physics of Covered Surfaces, I. Adsorb- ate Layers on Surfaces, Landolt-Boenstein Vol- ume III/42 A2, Chap. 4.5 1-68 ed. H. P. Bonzel ¥ “Ethylene adsorption on clean and oxygen cov- ered flat and stepped Ag(100),” L. Vattuone, L. Savio, M. Rocca, J. Mod. Phys., submitted ¥ “MgO/Ag(100): confined vibrational modes in the limit of ultrathin films,” L. Savio, E. Celasco, L. Vattuone, M. Rocca, P. Senet, Phys. Rev. B, sub- mitted ¥ “Direct access into subsurface sites in gas-sur- face interaction: O2/Ag(210),” L. Vattuone, L. Savio, M. Rocca, submitted ¥ “Oxygen vibrations in O at Ag(001),” D. Loffreda, A. Dal Corso, S. Baroni, L. Savio, L. Vattuone, M. Rocca, submitted ¥ “Enhanced hydrolysis at monolayer MgO films,” L. Savio, E. Celasco, L. Vattuone, M. Rocca, sub- mitted New Book: ¥ “Spontaneous spatial alignment of polymer cylin- Axel Groß drical nanodomains on silicon gratings,” D. Sun- drani, S. J. Sibener, Macromolecules, in press Theoretical Surface Science - ¥ “Reactive deposition of silicon nanowires tem- A Mircoscopic Persective plated on a stepped nickel surface,” Y. Wang, S. J. Sibener, J. Phys. Chem. B, in press Springer, Autumn 2002 49.95, ISBN 3-540-43903-X •“Temperature dependent morphological evolu- tion of HOPG graphite upon exposure to hyper- thermal O(3P) atoms,” K. T. Nicholson, T. K.

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American Physical Society March Meeting March 3-7, 2003 Austin, Texas

Focus Topic Symposium on “Structure and Properties of Organic Thin Films”

Organizer: Hai-Lung Dai (U. Pennsylvania) and Giacinto Scoles (Princeton U.)

Description: This symposium on multiplayer thin films and self-assembled monolayers of organic molecules deposited on metal, including Hg, semiconductor and insulator surfaces will focus on their structure, character- ization, and properties. The use of X-ray diffraction, atom and electron scattering, nonlinear optical spectros- copy, scanning microscopy, and other newly developed techniques for the characterization of the organic thin film structure and properties will be examined. The dynamics and kinetics concerning film growth and assem- bly, crystallization and nucleation, and morphology and polymorphism will be discussed. Focuses on properties include conductivity, hyper polarizability, exciton formation and carrier dynamics, lattice relaxation dynamics, optical and luminescence properties, and reactivity within the films.

Invited speakers: Eric Borguet, University of Pittsburgh Loredana Casalis, Elettra Synchrotron, Trieste, Italy Hai-Lung Dai, University of Pennsylvania Bj¿rk Hammer, Aarhus University, Denmark Gang-Yu Liu, University of California, Davis Helmut Möhwald, Max-Planck-Institute of Colloids and Interfaces, Germany Annabella Selloni, Princeton University Steven Sibener, University of Chicago Gabor Somorjai, University of California, Berkeley John Yates, University of Pittsburgh Kathryn J. Wahl, Naval Research Laboratory Robert Wolkow, National Research Council, Canada

http://www.aps.org/meeting/MAR03/

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Division of Chemical Physics March Meeting 2003 Symposium - Austin Texas "Dynamics, Assembly, Reactivity and Function Across Extended Length-scales" Organizer: Steven J. Sibener, The University of Chicago

This symposium will explore current issues in the assembly, chemical and physical properties, and dynamics of low-dimensional and confined systems across extended length-scales. Experiment, theory, and simulation papers are solicited for the following sessions which span phenomena encompassing atomic, molecular, supramolecular, nano- and micron length-scales:

Session I: Atomic Manipulation and Dynamics Session II: Molecular Assembly Session III: Cluster Materials and Bucky Media Session IV: Complex Organic and Polymeric Systems Session V: Organic/Inorganic/Bio Hybrid Systems

Invited Speakers: Paul F. Barbara, Univ. of Texas, Austin Moungi G. Bawendi, MIT Stacey F. Bent, Stanford Hongjie Dai, Stanford Don Eigler, IBM,,Almaden George Flynn, Columbia University Robert J. Hamers, Univ. of Wisconsin, Madison Wilson Ho, Univ. of California, Irvine Josef Michl, Univ. of Colorado, Boulder Paul Weiss, Penn State University

Steven J. Sibener Carl William Eisendrath Professor Director, The James Franck Institute

The James Franck Institute The University of Chicago 5640 South Ellis Avenue Chicago, IL 60637 USA

e-mail: [email protected] voice: +001 773-702-7193 fax: +001 773-702-5863/4180 Group Web Site: http://www.sibener-group.uchicago.edu MRSEC Web Site: http://www.mrsec.uchicago.edu/mrsec/ MURI Space Materials Web Site: http://www.spacematerialsmuri.uchicago.edu/

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POSTDOCTORAL RESEARCH POSITION University of Southern California, Los Angeles and ETH, Zürich, Switzerland

Surface Science Experiments to Improve the Understanding of Methanol Synthesis from CO Over Promoted Pd/Si02 Catalysts

A postdoctoral position is available in the research laboratory of Professor Bruce Koel to carry out vibrational studies of chemical reactions at surfaces. We are seeking outstanding individuals with a strong experimental background in HREELS and/or FTIR (IRAS) to study adsorbate bonding and geometry on single crystal sub- strates. A preference exists for expertise in IRAS. Other experimental tools that will be used include AES, LEED, UPS, XPS, ISS, and TPD. Experience with several of these techniques and surface science experimen- tal methods is required. This position offers the exciting opportunity to join an interdisciplinary joint research effort between our labora- tory and Professor Roel Prins ([email protected]) at the ETH in Zurich in the Department of Physical Chemistry. The successful applicant must agree to work for two or three months in Zurich at the beginning, pri- marily on the catalysis-related issues of the project, and after having acquainted themself with the subject and the way we see it, they will come to Los Angeles to start surface science model experiments to help explain the catalysis results. Salaries are very competitive. The position is available immediately although the starting date is flexible. The appointment will be for one year initially and is renewable for a second year. Current PhD's and graduate stu- dents within six months of receiving their degrees are encouraged to apply. Candidates should send via e-mail: (i) a letter detailing their qualifications, (ii) CV or resume, (iii) publication list, and (iv) names, phone no.’s, and email addresses of two professional references.

For more information, please see our web page at http://www-rcf.usc.edu/~koel/ or contact us at [email protected] or by phone at +100 213 740-4126

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WESTFÄLISCHE WILHELMS-UNIVERSITÄT MÜNSTER

A Graduate Student position is available in the group of Prof. Dr. H. Zacharias at the University Münster:

Experiments with femtosecond laser generated soft and hard x-ray radiation

Coherent soft x-ray radiation with a few femtosecond duration and photon energies up to 110 eV are generated by High Harmonic radiation. Incoherent hard x-ray pulses with pulse lengths of a few 100 fs are generated in laser produced plasmas. This short wavelength radiation is intended to be used for x-ray microscopy and sur- face experiments. The inherent time resolution will be exploited to investigate dynamic processes on surfaces, like reactions and phase transitions. X-ray laboratory diagnostics relevant for applications will be developed. The project is in an early stage. In the frame of a Ph.D. thesis the experimental techniques should be improved and the efficiency of the x-ray yield increased.

The interested applicants should contact:

Prof. Dr. H. Zacharias Physikalisches Institut Universität Münster Wilhelm-Klemm-Str. 10 D-48149 Münster Germany phone: +49 (0)251/ 8 333 609 e-mail: [email protected] additional information: http:// www.uni-muenster.de/Physik/Zacharias

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RHEINISCHE FRIEDRICH-WILHELMS-UNIVERSITÄT BONN INSTITUT FÜR PHYSIKALISCHE UND THEORETISCHE CHEMIE POSTDOCTORAL POSITION

A postdoctoral position is available in the surface science group of Prof. Klaus Wandelt. The work will be focused on a joint German-French research project on the Molecular scale reactivity at bimetallic surfaces. The target reactions will be the selective hydrogenation of unsaturated aldehydes and the selective oxidation of traces of CO in hydrogen. The project will conducted in close cooperation with our partners in France and will include UHV and high-pressure experiments as well as theoretical studies. The work in Bonn will be focused on high-resolution electron energy loss spectroscopy (HREELS) and STM investigations of the reactions at a molecular scale. We are looking for a person with a Ph.D. in Physics or Physical Chemistry and a strong back- ground in scanning tunneling microscopy (STM) and UHV technology. The primary task of the candidate in the initial period will be the upgrade of an existing UHV-STM to variable temperature operation. The initial appoint- ment will be for one year but the funding of the project will allow for a total of two years. Contact address:

Prof. Dr. Klaus Wandelt ([email protected]) Dr. Conrad Becker ([email protected]) Institut für Physikalische und Theoretische Chemie Universität Bonn Wegelerstr. 12 D-53115 Bonn, Germany

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Gas-Surface News

Postdoctoral Positions

LABORATORY FOR MOLECULAR ROBOTICS University of Southern California, SAL 202 Los Angeles, CA 90089-0781 Internet: [email protected] Telephone: (213) 740-4502 Fax: (213) 740-7512 WWW: http://www-lmr.usc.edu/~lmr

The Laboratory for Molecular Robotics (LMR) at the University of Southern California has immediate postdoc- toral openings for research on nanorobotics. A primary goal of a new 4-year project (in collaboration with Profs. Bruce Koel1 and Mark Thompson,2 both in the Depts. of Chemistry and Materials Science) is to design and implement a simple, self-propelling robot with overall dimensions at the micron or submicron scale, and built from nanoscopic components. The research involves the development of new nanosensors, controls and actu- ators, and the integration of molecular machines (such as the light-driven machines being built at several labo- ratories worldwide) into systems that mimic the capabilities of (non self-reproducing!) bacteria. A background in chemistry is required and familiarity with SPMs is desirable. Experience in molecular-machine development would be extremely valuable. A background in electroactive polymers or bio-inspired assembly would also be of particular interest. We are seeking outstanding individuals to join a highly interdisciplinary group. Good communication skills and the ability and willingness to work with colleagues in different disciplines are important. The initial appointment is for one year, renewable for one or more years. Salary and conditions are very com- petitive. LMR conducts leading-edge research in nanorobotics. For more information, please see our web page at http:/ /www-lmr.usc.edu/~lmr or contact us at [email protected] or by phone at (213) 740-4502. Please send resume including addresses (preferably e-mail) for 3 references to the e-mail address above or to

Prof. A. Requicha, Director Laboratory for Molecular Robotics University of Southern California 941 West 37th Place, SAL 300 Los Angeles, CA 90089-0781, USA

1 Physical Chemistry, Surface Science; http://chem.usc.edu/faculty/Koel.html 2 Inorganic Chemistry; http://chem.usc.edu/faculty/Thompson.html

13 Gas-Surface News

7 European research groups involved in fundamental and applied, experimental and theoretical aspects of surface science and heterogeneous catalysis are announcing Research training positions for Young Researchers within the EUROPEAN RESEARCH TRAINING NETWORK

SURFACE ACTIVE SITES & EMISSION CONTROL CATALYSIS ❀ 1 to 4-year positions, Ph.D. or post-doc ❀

❀ You are welcome to apply NOW (autumn 2002)! ❀ ❀ To apply, contact any of the team leaders. ❀

Team leader Laboratory and e-mail Techniques Prof. Kersti Hermansson Materials Chemistry, The Ångström Laboratory, Uppsala University, Theoretical calc. (project coordinator) Sweden, http://www.teoroo.mkem.uu.se, [email protected] (QC, MD, LD) Dr. Roger Nix Chemistry Department, Queen Mary, University of London, UK, IRAS, XPS, TPD http://www.chem.qmul.ac.uk, [email protected] Prof. Helmut Weiss Chemisches Institut, Otto-von-Guericke Univ., Magdeburg, Germany, HAS, LEED, http://davisson.nat.uni-magdeburg.de, [email protected] ATLEED Prof. Declan Burke Chemistry Department, University College Cork, Ireland, Electrochemistry http://chemweb.ucc.ie, [email protected] Prof. Michael Bowker Centre for Surface Science and Catalysis, The University of Reading, UK, STM, Pulsed http://www.chem.rdg.ac.uk/dept/catrg/catrg.html, [email protected] Flow Reactor Prof. Anders Lund Department of Physics and Measurement Technology, Linköping Electron spin University, Sweden, http://www.ifm.liu.se/chemphys/, [email protected] resonance (ESR) Prof. Stephen Holloway Surface Science Research Centre, The University of Liverpool, UK, Trajectory and

http://www.ssci.liv.ac.uk [email protected] wave-packet calc.

SCENTIFIC CONTENTS OF THE NETWORK PROJECT: Our Research goal is to explore the Surface science and functionality of metal oxide surfaces with and without a catalytically active metal present. For this purpose, we – and you – will be using and developing the most modern and advanced experimental and theoretical techniques. In particular, we will study: • METAL OXIDE SURFACE STRUCTURE We will extend both the experimental and theoretical methods to study conditions which reflect catalytically operating conditions. • SURFACE DYNAMICS The magnitude and nature of the surface ion motion at different temperatures will be studied, as well as the role of surface dynamics on the catalytic processes. • MOLECULE-SURFACE REACTION DYNAMICS • IDENTIFICATION OF ACTIVE SITES The presence & role of different types of surface active sites will be explored as well as the effect of temperature on the presence and nature of the active sites.

More information at the Network web-site: www.teoroo.mkem.uu.se/EU-surface/ EU rules: To apply for a post-doc or a Ph.D. position you must (i) hold a degree which quailifies to embark on Ph.D. studies – or for a post-doc position – hold a Ph.D. degree, (ii) be a citizen of an EU Member state or of an Associated state (Bulgaria, Cyprus, Czech Republic, Estonia, Hungary, Latvia, Lithuania, Malta, Poland, Romania, Slovakia, Slovenia, Lichtenstein, Iceland, Israel, Norway), or have resided in a Member state for at least five years, (iii) must not be a citizen of the country where the Network team you want to work with is located, (iv) must not be over 35 years of age at the time you begin your research training in the Network.

14 Gas-Surface News

POSTDOCTORAL POSITION UNIVERSITY OF NOTRE DAME Notre Dame, IN, USA

A postdoctoral position in experimental ion/surface reaction dynamics is immediately available in the laboratory of Prof. Dennis C. Jacobs. Laser ionization methods (REMPI) capable of preparing aligned molecular ions in selected rovibronic states are utilized. The state-selected ions are accelerated to hyperthermal energies (5-100 eV) and collide with well-characterized single-crystal surfaces under UHV conditions. Novel ion imaging detection allows for simultaneous mass-, charge-, velocity-, and angular- resolution of the scattered products. Detailed mechanisms for electron transfer, dissociation, and atom abstraction reactions are probed by measuring how the reaction probability depends on the collision energy, angle-of-incidence, initial molecular electronic state, initial vibrational level, incident molecular alignment, and the surface adsorbate structure.

Candidates with previous experience using any of the following (pulsed lasers, charged particle optics, ultra- high vacuum surface science techniques) are strongly encouraged to apply. Applicants should send a curriculum vitae and arrange for two letters of recommendation to be sent to:

Prof. Dennis C. Jacobs Department of Chemistry 251 Nieuwland Science Hall University of Notre Dame Notre Dame, IN 46556 USA Email: [email protected]

A more complete description of the research group can be found at:

15

Diary Page

29th November 2002 “Towards an Understanding of Simple Catalytic Reactions,” TASC, Elettra Synchrotron Trieste-Basovizza For the complete programme please contact the web site: http://server 1.Þsica.unige.it/ ~rocca/Workshop02/Programme.htm, organizer is Mario Rocca, email: rocca@Þsica. unige.it, Participation is free.

16th-21st February 2003 Gordon Research Conference on Chemical Reactions at Surfaces, Ventura, California Conference application information can be obteined from the GRC web site or: Gordon Research Conferences, University of Rhode Island, PO Box 984, West Kingston, RI 02892- 0984, USA, +01 401 783-4011, email: [email protected].

3rd-7th March 2003 American Physical Society March Meeting, Austin, Texas http://www.aps.org/meeting/MAR03/ Focus Topic Symposium on “Structure and Properties of Organic Thin Films,”organizers are Hai-Lung Dai (U. Pennsylvania), Giacinto Scoles (Princeton U.) Division of Chemical Physics, 2003 Symposium “Dynamics, Assembly, Reactivity and Function across Extended Length-Scales”, organizer is Steven J. Sibener (University of Chicago), e-mail: [email protected]

31st March - 4th April 2003 The Third San Luis Symposium on Surfaces, Interfaces and Catalysis, Mérida, Venezuela More information can be found at the web site: http://www.chem.ucr.edu/Zaera/SanLu- isIII/, organizer is Francisco Zaera, Department of Chemistry, University of California, Riverside, CA 92521, USA, phone: +01(909)787-5498, fax: +01(909)787-3962, email: fran- [email protected], web site: http://www.chem.ucr.edu/Zaera/lab.html