No abstract

1,3-Thiazole is found to be nearly perpendicularly adsorbed on Cu(100), with the N atom attaching to an atop site and an adsorption energy of ∼19.5 kcal•mol −1 . The N−C−S moiety of the adsorbed 1,3-thiazole has a larger change in bond length as compared to a free 1,3-thiazole molecule. The adsorbed 1,3-thiazole can decompose below 200 K, forming atomic S and −CHCHNCH−. A small amount of R−S− (R: CHCHNCH) is detected on the surface at 200 K. Complete desulfurization of the 1,3-thiazole occurs at 400 K. Further reaction of the −CHCHNCH− produces H 2 and HCN at higher temperatures. In the presence of adsorbed oxygen atoms(O/Cu(100)), new disulfide intermediates (R−S−S−R, R: CHCHNCH) from the thiazole reaction are measured at 300 K and can further decompose into atomic S and −CHCHNCH− at 400 K. In addition, other surface species of −NCO and >CCO are also observed at 500 K. These species eventually react to generate H 2 O, CO, CO 2 , and N 2 . Further calculations indicate that the S−CHN bond of 1,3thiazole would break preferentially, as compared to the S−CHCH bond, in the decomposition process on Cu(100).