Characterization of nanoscale adhesion between a fluoroalkyl silane monolayer and a silicon AFM tip. Complex character of the interaction potential

Adhesion force versus loading rate curve for the nanoadhesion between a silicon tip and fluoroalkyl silanes. The bi-logarithmic dependence suggests a two-transition state interaction potential. The appearance of the inner transition state can be explained by superposition of the attractive van der Waals forces and repulsive elastic forces.