SCANNING-TUNNELING-MICROSCOPY STUDY OF C(2X4)-NO PT(001)/

A structure of NO adsorbed on a Pt(001)-hex R0.7 degrees surface at 30 0 K was investigated by atomically resolved scanning tunneling microsc opy (STM) in an ultra-high vacuum environment. STM images of SO on a P t(001) surface at 300 K showed a simple c(2 x 4)-NO superstructure cor responding to a saturation coverage of 0.25. Our STM observation diffe red from the previous c(2 x 4) models for the NO adlayer with a satura tion coverage of 0.5. At 90 K, extremely small and one-dimensionally g rown domains of a quasi-c(2 x 4) adlayer were observed as clustered is lands with a stripe structure of the bare Pt(001)-hex R0.7 degrees sur face.