Reflection infrared study of the Xe-CO interaction on Pt(335): A new method for site assignment of chemisorbed species

Journal Article · Sat Oct 01 00:00:00 EDT 1994 · Langmuir; (United States)

DOI:https://doi.org/10.1021/la00022a046· OSTI ID:7071089

Xu, J; Henriksen, P N; Yates, Jr, J T ^[1]

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1. Univ. of Pittsburgh, PA (United States)

The interaction of CO and Xe on Pt(335)[Pt4(111)x(100)] has been studied by temperature-programmed desorption (TPD) and infrared reflection-absorption spectroscopy (IRAS). TPD results show desorption peaks at approximately 400 K and approximately 500 K from the pure CO layer. The high-temperature peak is related to CO adsorbed on step sites, while the low-temperature peak is related mainly to CO adsorbed on terrace sites. IRAS studies, performed on CO layers after annealing to 290 K, show four subsequently appearing vibrational modes: approximately 2075 and approximately 1880 cm[sup [minus]1] for low [theta][sub CO], and approximately 2092 and approximately 1900 cm[sup [minus]1] for high [theta][sub CO]. Experiments involving Xe coadsorption and isotopic CO site exchange have been conducted, and the four vibrational modes are assigned to terminal and bridged CO adsorbed on step sites for low [theta][sub CO] and on terrace sites for high [theta][sub CO], respectively. The stepwise sequence for CO adsorption on Pt(335) is thus: terminal-bound CO followed by bridge-bound CO on step sites at low [theta][sub CO]-CO, then terminal-bound CO followed by bridge-bound CO on terrace sites at high [theta][sub CO]. 24 refs., 5 figs.

• OSTI ID: 7071089
• Journal Information: Langmuir; (United States), Journal Name: Langmuir; (United States) Vol. 10:10; ISSN LANGD5; ISSN 0743-7463
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400102 -- Chemical & Spectral Procedures
400201* -- Chemical & Physicochemical Properties
ABSORPTION SPECTROSCOPY
ADSORPTION
CARBON COMPOUNDS
CARBON MONOXIDE
CARBON OXIDES
CHALCOGENIDES
COHERENT SCATTERING
DESORPTION
DIFFRACTION
ELECTRON DIFFRACTION
ELECTRON SPECTROSCOPY
ELEMENTS
ENERGY LEVELS
EXCITED STATES
FLUIDS
GASES
INFRARED SPECTRA
METALS
NONMETALS
OXIDES
OXYGEN COMPOUNDS
PHOTOELECTRON SPECTROSCOPY
PLATINUM
PLATINUM METALS
RARE GASES
SCATTERING
SORPTION
SPECTRA
SPECTROSCOPY
TRANSITION ELEMENTS
VIBRATIONAL STATES
XENON