Scanning Probe Microscopy Study of Layered Dichalcogenide ReS2

Abstract

The surface of the layered chalcogenide ReS{sub 2} was examined by atomic force microscopy (AFM) and scanning tunneling microscopy (STM), and the structure of ReS{sub 2} was determined by single crystal X-ray diffraction measurements. The observed atomic-resolution AFM and STM images were analyzed by calculating the total and partial electron density distributions [{rho}(r{sub o}) and {rho}(r{sub o}e{sub r}) respectively] of a single ReS{sub 2} layer taken from the bulk crystal structure. Our results show that the STM images are associated with the surface S atoms. The {rho}(r{sub o},e{sub f}) plots of the two tunneling processes differ in topography from the {rho}(r{sub o}) plot so that the surface atomic structure cannot be unambiguously deduced from the analysis of atomic-resolution STM images alone. Calculations of the {rho}(r{sub o}) and {rho}(r{sub o},e{sub f}) plots are essential for properly interpreting the atomic-resolution AFM and STM images. 27 refs., 11 figs., 1 tab.