The energy and angular dependence of dissociative hydrogen adsorption on Cu(110)

• Published in: Chemical physics letters Vol. 160; no. 3; pp. 331 - 334
• Main Authors: Hayden, B.E., Lamont, C.L.A.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 11.08.1989; Elsevier Science
• Subjects: Applied sciences; Chemistry; Exact sciences and technology; General and physical chemistry; Metals. Metallurgy; Solid-gas interface; Surface physical chemistry; Inorganic adsorbate; Translational energy; Adsorption; Hydrogen; Metallic adsorbent; Crystal face; Transition metal; Copper; Experimental study; Angle of incidence; Low temperature
• ISSN: 0009-2614; 1873-4448
• DOI: 10.1016/0009-2614(89)87605-5

The dissociative sticking probability ( S 0) of H 2 on Cu(110) for surface temperatures in the range 140 < T s < 250 K has been measured as a function of translational energy ( E i) and angle (φ) of the incident molecules. The onset of sticking is sharp and occurs when the normal component of translational beam energy E ⊥ ≈200 meV. At 260 meV, S 0 is still only 2 × 10 −3 but is rising quickly. A “near” normal energy scaling for S 0 is exhibited in the measured range 180 < E ⊥ < 260 meV. Measurements of S 0 as a function of incident angle reveal an angular-dependent sticking probability which is strongly peaked (cos 15φ) towards the surface normal. These results indicate that the activation barrier to dissociative adsorption is significantly higher than previously believed.