Scanning Tunneling Microscopy

STM is the basis of a powerful "surface structure" apparatus that incorporates an STM into a UHV chamber that also contains complementary facilities for AES, XPS, LEED, FTIR, and TPD. We use a "single-tube piezo type" STM with a sample holder that has low (LHe) temperature capabilities. We continue to develop our variable-temperature STM capabilities, because this is essential for us to do our work as chemists to measure reaction kinetics, surface diffusion, phase changes, and a wide variety of other temperature-dependent phenomena. Our initial measurements have concerned the atomic structures of ordered intermetallic compounds or alloys of two metals and the ordered oxide layers formed upon oxidation of these substrates. Also of interest is the growth and morphology of ultrathin metal films deposited and grown on a second-metal substrate. Questions of interest include the nature of 2-dimensional and 3-dimensional clustering and island growth, and adsorbate-induced surface reconstructions.