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Imaging probes force regimes

On the other hand, AFM exploits the forces which exist between atoms and molecules. The force exerted upon a tip mounted onto a cantilever with a known spring constant is monitored as the tip passes over the surface. The cantilever deflects during the scan and from the measurement of these an image of the surface topography is obtained. All types of materials experience these forces so the AFM is not limited to conductors. There are two regimes of force which can be felt by the probing tip. If the tip is scanned extremely close to the surface, the force F(r) will be expressed as... [Pg.326]

This is largely because the two techniques share the same key elements - a passivated tip (H-passivated in the case of Termirov et al. s results) and operation within the Pauli repulsion regime - although the contrast mechanisms are of course rather different. For STHM, the passivated tip translates variations in tip-sample force into a modulation of the junction conductance. As can be seen from Fig. 10(b) the image resolution far exceeds that observed in conventional STM because the latter is sensitive only to variations in electron density in a relatively narrow energy window close to the Fermi level. In STHM, as pointed out by Temirov et it is variations in the total electron density - and the information on chemical structure embedded within it which are probed. [Pg.130]


See other pages where Imaging probes force regimes is mentioned: [Pg.560]    [Pg.35]    [Pg.36]    [Pg.240]    [Pg.909]    [Pg.456]    [Pg.908]    [Pg.590]    [Pg.556]    [Pg.286]    [Pg.932]    [Pg.76]    [Pg.146]    [Pg.465]    [Pg.80]    [Pg.63]    [Pg.649]    [Pg.55]    [Pg.67]    [Pg.79]    [Pg.34]    [Pg.188]    [Pg.187]    [Pg.78]    [Pg.2]    [Pg.2898]   


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