Thermally-induced and electron-induced chemistry of CF[sub 3]I on Ni(100)

Journal Article · Wed Jan 11 04:00:00 EST 1995 · Journal of the American Chemical Society; (United States)

DOI:https://doi.org/10.1021/ja00106a050· OSTI ID:6868067

Jensen, M B; Thiel, P A ^[1]

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1. Iowa State Univ., Ames, IA (United States)

We have investigated the thermally-induced and electron-impact-induced chemistry of CF[sub 3]I on Ni(100) following adsorption at 100 K. The data support a model for the thermally-induced chemistry, in which CF[sub 3]I dissociates to CF[sub 3] and I, either upon adsorption or at slightly-elevated temperatures. Most CF[sub 3] decomposes to adsorbed C and F. Above 75% saturation of the first layer, the availability of surface sites for decomposition decreases to a level where some adsorbed CF[sub 3] remains intact and desorbs as such. Bombardment of multilayer CF[sub 3]I by low-energy electrons introduces new chemistry. Electron-induced decomposition (EID) of the parent molecule occurs through both C-I and C-F bond scission, with a measured cross section of 1.5 x 10[sup -16] cm[sup 2] (upper limit). Thermally-induced desorption from the electron-bombarded surface indicates a number of EID fragment reactions, most notably carbon-carbon bond formation, as evidenced by C[sub 2]F[sub 3]I[sup 1], C[sub 2]F[sub 4][sup +], C[sub 2]F[sub 5][sup +], C[sub 3]F[sub 3][sup +], and C[sub 4]F[sub 7][sup +]. To our knowledge, this is the first report of C-C bond formation in small fluorocarbons adsorbed on metal surfaces. 36 refs., 13 figs.

• DOE Contract Number: W-7405-ENG-82
• OSTI ID: 6868067
• Journal Information: Journal of the American Chemical Society; (United States), Journal Name: Journal of the American Chemical Society; (United States) Vol. 117:1; ISSN JACSAT; ISSN 0002-7863
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
664300 -- Atomic & Molecular Physics-- Collision Phenomena-- (1992-)
665300 -- Interactions Between Beams & Condensed Matter-- (1992-)
74 ATOMIC AND MOLECULAR PHYSICS
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
CHEMICAL BONDS
CHEMICAL REACTIONS
COLLISIONS
DECOMPOSITION
ELECTRON COLLISIONS
ELEMENTS
METALS
NICKEL
ORGANIC COMPOUNDS
ORGANIC FLUORINE COMPOUNDS
ORGANIC HALOGEN COMPOUNDS
TRANSITION ELEMENTS