title: Electrostatic force curves in finite-size-ion electrolytes.
abstract: We obtain analytical expressions for electrostatic forces between an atomic force microscope tip and a sample immersed in an electrolyte. These simple expressions relate force to tip-sample separation explicitly incorporating tip size, solvent ion size, and solvent ion concentration. If the ions are much smaller than the tip-sample gap, the force decays monotonically, a consequence of the corresponding monotonic decays of the correlation function in the Debye-Hückel context. If the ions are of size comparable to the tip-sample gap, then oscillations appear superimposed on the overall decay, a consequence of the geometric mismatch between ion cluster size and the gap size.
authors: Department of Physics, Yeshiva University , New York, New York 10033, United States.
authors: Fredy R
authors: FR
authors: Zypman
authors: Steven J
authors: SJ
authors: Eppell
mesh_terms: D004573:Electrolytes; D018625:Microscopy, Atomic Force / Q000379:methods*; D055672:Static Electricity
chemical_list: D004573:Electrolytes