The Combined Role of Thermodynamics and Kinetics in the Growth of Colloidal B...
Chem 823 presentation
1. Chemical identification of individual surface atoms by Atomic Force Microscopy Sugimoto, Pou, Abe, Jelinek, Peres, Morita & Custance Nature 446, 64-67, 2007 Vivek J P Chem 823 presentation March 2 nd 2007
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4. Atomic Force Microscope Modes of operation : Static Dynamic Amplitude Modulation Frequency modulation Probing the force between sharp tip and sample Sample + holder cantilever probe Laser Photo detector mirror Electronic control system
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6. Chemical identification of individual atoms One of the thorniest problems in surface science. In principle, dynamic force microscopy should make it possible (motivation of the present work) Determining Chemical composition of nanostructures remains a challenge (especially for insulators)
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9. Discussions on the work (contd…) The force curves of Sn/Si and Pb/Si before (a&c) and after (b&d)normalization (Key step )
10. Discussions on the work (contd… ) Theoretical modeling for the interaction between tip and surface Force curves before normalization Force curves after normalization
11. Discussions on the work (contd…) (a) Topographic image of a surface alloy composed by Si, Sn and Pb atoms (b) Height distribution of the atoms in (a) (c) and (d): Local chemical composition
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16. Sample + holder cantilever probe Laser Photo detector mirror Electronic control system
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