The adsorption structure of 2,5-dihydrothiophene on Mo(110)-(4 × 1)-S: ring orientation as determined by NEXAFS

Near edge X-ray adsorption fine structure (NEXAFS) data have been used to determine the orientation of 2,5-dihydrothiophene on Mo(110)-(4 × 1)-S at saturation coverage (θ ∼ 0.3). The C;CCC plane is nearly perpendicular to the surface, tilting ∼ 9° away from surface normal based on an analysis of the polarization dependence of the C(1s) → π* resonance intensity. Furthermore, the π* resonance is very sharp indicating that the CC bond does not interact significantly with the molybdenum surface. The NEXAFS data corroborate earlier conclusions regarding the ring orientation and lack of π bonding with the surface derived from high resolution electron energy loss data. © 1993.