Dynamic SFMwith true atomic resolution on alkali halide surfaces

Large-amplitude dynamic force microscopy is used to study alkali halide surfaces. The {001} cleavage faces of NaF, RbBr, LiF, KI and NaCl could be atomically resolved with excellent stability. In all cases the observed lattice periods correspond to the bulk lattice of equally charged ions. The resonance frequency shift and the atomic corrugation amplitude tend to increase after successive tip crashes. This behaviour is explained by analogy with scanning tunneling microscopy. In addition, the mean atomic corrugation is found to be comparable to the difference between the anion and cation ionic radii. © 1998 Springer-Verlag.