We report scanning tunneling microscopy and complementary spectroscopic mea
surements on TiO2(110) surfaces. We show data on (i) a surface restructurin
g process that results from annealing in oxygen; (ii) Pt clusters, grown at
room temperature and encapsulated upon high temperature annealing; and (ii
i) adsorption of sulfur. In each case, heavily reduced, dark crystals show
a very different behavior than more stoichiometric, light Glue ones.