Photodissociation and photodesorption of O2 adsorbed on Pd(111)

doi:10.1016/0039-6028(92)91256-B

Surface Science

Volumes 269–270, 15 May 1992, Pages 235-246

https://doi.org/10.1016/0039-6028(92)91256-B Get rights and content

Abstract

The dynamics of the UV-photochemistry of molecularly adsorbed oxygen on Pd(111) has been studied using pulsed laser light between 3.9 and 6.4 eV photon energy. Photodissociation to form atomic surface oxygen and photodesorption of O₂ are the primary processes. The latter is characterized by a translational energy of about 800 K indicating non-thermal desorption. Since the photolytically formed atomic oxygen competes with the molecular adsorbate for binding sites some of the latter is displaced. This manifests itself in a conversion process between adsorbate states and in a desorption channel with a translational energy of 120 K indicating accommodation to the surface temperature. The cross sections for all processes rise exponentially from 3.9 to 6.4 eV by a factor of 38.

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¹: Permanent address: NEC Corporation, Microelectronics Research Laboratories, 34 Miyukigaoka, Tsukuba 305, Japan.

²: Present address: Department of Chemistry, University of Texas, Austin, TX 78712, USA.

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Photodissociation and photodesorption of O2 adsorbed on Pd(111)

Abstract

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Surf. Sci. Rep.

Surf. Sci.

Surf. Sci.

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Surf. Sci.

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Annu. Rev. Phys. Chem.

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Phys. Rev. Lett.

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Photodissociation and photodesorption of O₂ adsorbed on Pd(111)