A solid-state [sup 13]C NMR study of the molecular motion of ethylene adsorbed on a silver surface

Journal Article · Wed Jan 13 00:00:00 EST 1993 · Journal of the American Chemical Society; (United States)

DOI:https://doi.org/10.1021/ja00054a030· OSTI ID:6483121

Wang, Jianxin; Ellis, P D ^[1]

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1. Univ. of South Carolina, Columbia (United States)

The reorientation of ethylene on a silver catalyst surface has been studied by solid-state [sup 13]C NMR. The static cross-polarization spectra at different temperatures have been measured. Different jump site models are proposed to simulate the experimental results. It was found that the models involving a low number of jump sites are more sensitive to the experimental details. By comparison of the simulated and experimental results, the 6- and 4-site jump models are chosen as the most satisfactory model to fit the experimental spectra. On the basis of this representation, the activation energy derived for the jump process is 4.3 kJ/mol. From the simulated results, it was concluded that the symmetry axis for the motion of the ethylene at low temperatures ([minus]173 to ca. [minus]45[degrees]C) is perpendicular to the plane of the ethylene molecule. At higher temperatures motion about other axes is initiated such that at room temperature a nearly isotropically averaged [sup 13]C shielding tensor is observed. 20 refs., 9 figs.

• OSTI ID: 6483121
• Journal Information: Journal of the American Chemical Society; (United States), Vol. 115:1; ISSN 0002-7863
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
ETHYLENE
SORPTION
SILVER
SORPTIVE PROPERTIES
ACTIVATION ENERGY
CARBON 13
CATALYSTS
NUCLEAR MAGNETIC RESONANCE
POLARIZATION
ALKENES
CARBON ISOTOPES
ELEMENTS
ENERGY
EVEN-ODD NUCLEI
HYDROCARBONS
ISOTOPES
LIGHT NUCLEI
MAGNETIC RESONANCE
METALS
NUCLEI
ORGANIC COMPOUNDS
RESONANCE
STABLE ISOTOPES
SURFACE PROPERTIES
TRANSITION ELEMENTS
400201* - Chemical & Physicochemical Properties