Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5425755 | Surface Science | 2006 | 8 Pages |
A scanning tunneling microscope that can be operated in ultra high vacuum (<10â9 Torr) as well as at high pressures (1 â 103 Torr) has been utilized to study the structures formed by cyclic C6 hydrocarbons adsorbed on a platinum (1 1 1) crystal surface. Catalytic reactions of cyclohexene were also studied in the presence of hydrogen at pressures (up to 200 mTorr) and 300 K-350 K temperature range. Cyclohexane and cyclohexene produced the same adsorbed structure, which is attributed to the partially dehydrogenated Ï-allyl (C6H9). 1,3-Cyclohexadiene produced structures similar to those produced by benzene. In contrast 1,4-cyclohexadiene forms a structure that we attribute to intact molecular 1,4-cyclohexadiene. During reaction the STM images appear disordered, indicative of rapid diffusion of surface species. Addition of 5 mTorr of CO stops the catalytic activity and forms an ordered structure on the surface.