{"93541":{"#nid":"93541","#data":{"type":"event","title":"(1129) Prof. Hannu Hakkinen, Univ of Jyv\u00e4skyl\u00e4","body":[{"value":"\u003Cp\u003EProf. Hannu Hakkinen, Univ of Jyv\u00e4skyl\u00e4, Finland\n\u003C\/p\u003E\n\u003Cp\u003EQuantum finite size effects in chemistry of nanoscale gold clusters\n\u003C\/p\u003E\n\u003Cp\u003EInvestigations of the physical and chemical properties of metal clusters are currently largely motivated by the question how their various remarkably size-dependent properties could be best utilized while the clusters are interacting with the environment, e.g., bound on or implanted in a support, or stabilized and surface-passivated by ligands. Understanding factors that dictate the stability, structure and function has relevance regarding atomic-scale design of components that could be of potential use in future nanotechnologies. To this end, spectroscopic tools and density functional theory calculations can provide valuable insights.\n\u003C\/p\u003E\n\u003Cp\u003EGold clusters with a size of just a few atoms, adsorbed on MgO\/Metal supports, have turned out to be paradigms to provide insight into the importance of quantum finite size effects in nanoscale chemistry - it has been demonstrated that by changing the size or elemental composition of the supported cluster even atom by atom one can quite dramatically affect the chemical properties of the cluster [1,2].\n\u003C\/p\u003E\n\u003Cp\u003EThis talk discusses some of our current theoretical efforts to further characterize MgO-supported Au clusters, motivated by recent high-resolution STM\/STS data on Au clusters grown on defect sites of MgO\/Mo and MgO\/Ag. [3] We discuss optical spectra [4,5] as well as structure and symmetries of the highest occupied and lowest unoccupied cluster valence electron states, confined spatially by the atomic geometry and energetically within the bandgap of MgO. [6] These states show well-defined symmetries, expected from the delocalized electron shell model for free Au clusters of similar size. [7,8] The metal support below an ultrathin MgO film turns the adsorbed gold clusters as singly charged anions, [9,10] consequently, a highly size-sensitive reactivity with oxygen is expected.\n\u003C\/p\u003E\n\u003Cp\u003E[1] H. H\u00e4kkinen et al., Angew. Chem. Int. Ed. 42, 1297 (2003).\u003Cbr \/\u003E\n[2] B. Yoon et al., Science 307, 403 (2005).\u003Cbr \/\u003E\n[3] M. Sterrer et al., Angew. Chem. Int. Ed. 45, 2630 (2006).\u003Cbr \/\u003E\n[4] M. Walter and H. H\u00e4kkinen, Phys. Rev. B 72, 205440 (2005).\u003Cbr \/\u003E\n[5] M. Walter, H. H\u00e4kkinen, J. Stanzel, M. Neeb and W. Eberhardt, Phys. Rev. B 76, 155422 (2007).\u003Cbr \/\u003E\n[6] M. Walter, P. Frondelius, K. Honkala, H. H\u00e4kkinen, Phys. Rev. Lett. 99, 096102 (2007)\u003Cbr \/\u003E\n[7] M. Walter and H. H\u00e4kkinen, Phys. Chem. Chem. Phys. 8, 5407 (2006). [8] B. Yoon et al., Chem. Phys. Chem. 8, 157 (2007).\u003Cbr \/\u003E\n[9] P. Frondelius, H. H\u00e4kkinen, K. Honkala, New Journal of Physics, 9, 339 (2007).\u003Cbr \/\u003E\n[10] P. Frondelius, H. H\u00e4kkinen, K. Honkala, Phys. Rev. B 76, 073406 (2007)\n\u003C\/p\u003E\n\u003Cp\u003EFor more information contact \u003Ca href=\u0022mailto:robert.whetten@chemistry.gatech.edu\u0022\u003EDr. Rob Whetten\u003C\/a\u003E (404-894-8255).\u003C\/p\u003E","summary":null,"format":"limited_html"}],"field_subtitle":"","field_summary":[{"value":"Prof. Hannu Hakkinen, Univ of Jyv\u00e4skyl\u00e4, Finland\n\nQuantum finite size effects in chemistry of nanoscale gold clusters","format":"limited_html"}],"field_summary_sentence":[{"value":"Prof. Hannu Hakkinen, Univ of Jyv\u00e4skyl\u00e4, Finland"}],"uid":"27275","created_gmt":"2007-11-27 01:00:00","changed_gmt":"2016-10-08 01:57:24","author":"Shirley Tomes","boilerplate_text":"","field_publication":"","field_article_url":"","field_event_time":{"event_time_start":"2007-11-29T14:00:00-05:00","event_time_end":"2007-11-29T15:00:00-05:00","event_time_end_last":"2007-11-29T15:00:00-05:00","gmt_time_start":"2007-11-29 19:00:00","gmt_time_end":"2007-11-29 20:00:00","gmt_time_end_last":"2007-11-29 20:00:00","rrule":null,"timezone":"America\/New_York"},"extras":[],"groups":[{"id":"85951","name":"School of Chemistry and Biochemistry"}],"categories":[],"keywords":[{"id":"89","name":"chemistry"}],"core_research_areas":[],"news_room_topics":[],"event_categories":[{"id":"1795","name":"Seminar\/Lecture\/Colloquium"}],"invited_audience":[],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[{"value":"\u003Cstrong\u003EShirley Tomes\u003C\/strong\u003E\u003Cbr \/\u003EChemistry \u0026amp; Biochemistry\u003Cbr \/\u003E\u003Ca href=\u0022http:\/\/www.gatech.edu\/contact\/index.html?id=st81\u0022\u003EContact Shirley Tomes\u003C\/a\u003E\u003Cbr \/\u003E\u003Cstrong\u003E404-894-0591\u003C\/strong\u003E","format":"limited_html"}],"email":[],"slides":[],"orientation":[],"userdata":""}}}