Organosulfur chemistry on tungsten(211) surfaces. 2. A comparison of benzene, thiophene, and tetrahydrothiophene

Adsorption of thiophene and pyridine on W(110)

“…The apparent discrepancy between the present work and Ref. [12] may either be due to differences in reactivity between the two tungsten planes or the different adsorption temperatures.…”

“…Preston and Benziger [12] investigated the adsorption of thiophene on W(2 1 1) at 250 K. In contrast to the present study, these authors observed some molecular thiophene desorption at 350 K when the surface was saturated with monolayer coverage. However, partial coverage (below 4 · 10 14 molecules/cm 2 ) gave complete decomposition of the chemisorbed layer upon heating.…”

“…With the exception of an investigation of thiophene on W(2 1 1) [12] and an FTIR spectroscopy study of pyridine on W(1 1 0) [13], this is the first comprehensive investigation of these adsorbates on tungsten.…”

A New Approach to Understand the Adsorption of Thiophene on Different Surfaces: An Atom Probe Investigation of Self-Assembled Monolayers

“…Tungsten (W) was initially chosen as a substrate, since it is used as a catalytic surface or additive, for example, in hydrodesulfurisation processes . Oxidation of the substrate changes the surface interactions with thiophene molecules . For example, Preston et al found that thiophene molecules do not dissociate from an oxidized W (211) surface, but rather desorb molecularly, indicating that the bond that is formed between the oxide layer and the thiophene is weaker compared to the nonoxidized W (211) surface.…”

Cycloaddition chemistry of thiophene on the silicon (111)-7×7 surface

“…Since the adatoms and rest atoms are both spatially and electronically inequivalent in nature, the present heterogeneous ͓4ϩ2͔ cycloaddition reaction may not be a concerted process although the concerted reaction is common in the gas or liquid phase. 55 A precursor-mediated chemisorption may be involved, similar to the case of benzene or chlorobenzene. 24,25 The reaction probably occurs through a short-lived monobonded state, subsequently the stable di-bonded thiophene on Si͑111͒-7ϫ7.…”