Time lags and V-V' steady states in the infrared laser induced decomposition of chlorodifluoromethane and chlorodifluoromethane-d1 under collisional conditions
摘要:
DOI:
10.1021/ja00375a013
作为产物:
描述:
三氟碘甲烷 在
Ni(111), D 作用下,
生成 四氟乙烯 、 四氟化碳 、 二氟甲烷 、 二氟甲烷-D2 、 alkaline earth salt of/the/ methylsulfuric acid
参考文献:
名称:
Adsorption and Reaction of Trifluoromethyl Iodide on Ni(111)
摘要:
We have investigated the surface chemistry of trifluoromethyl iodide adsorbed on Ni(111) under ultrahigh-vacuum conditions using temperature-programmed desorption, reflection absorption infrared spectroscopy, and Auger electron spectroscopy. Ni(111) activates both carbon-iodine and carbon-fluorine bonds in adsorbed CF3I. Atomic iodine desorbs from the surface near 975 K, and nickel fluoride, NiF2, desorbs near 820 K. Although the desorption temperatures for iodine and nickel fluoride are high, there is evidence that carbon-iodine and carbon-fluorine bonds are activated below room temperature. A small amount of fluorocarbon products containing CF2 and CF3 fragments desorb from the surface between 200 and 375 K. At higher temperatures, fluorine atoms recombine with adsorbed carbon to form CF4, which desorbs near 780 K. CF3I molecularly desorbs from the surface at high coverages with desorption rate maxima of 162 and 122 K for the monolayer and multilayer, respectively. Coadsorption of D atoms and CF3I results in the desorption of CD2F2 near 230 K and DF between 260 and 460 K. After desorption of the monolayer, the bands in the infrared spectrum are quite weak. The IR data suggest that very few fluorocarbon fragments are stabilized on the surface. In general, the data indicate that a large fraction of adsorbed CF3I decomposes to form atomic carbon, fluorine and iodine. A comparison of the reactions of CF3I on Ni to Ag, Pt and Ru shows that only Ni is etched under ultrahigh-vacuum conditions by CF3I.
Infrared Spectra and Electronic Structures of Agostic Uranium Methylidene Molecules
作者:Jonathan T. Lyon、Lester Andrews、Han-Shi Hu、Jun Li
DOI:10.1021/ic701786h
日期:2008.3.1
Through reactions of laser-ablated uranium atoms with methylene halides CH2XY (XY = F2, FCl, and Cl2), a series of new actinide methylidene molecules CH2UF2, CH2UFCl, and CH2UCl2 are formed as the major products. The identification of these complexes has been accomplished via matrix infrared spectra, isotopic substitution, and relativistic density functional calculations of the vibrational frequencies
Infrared Spectra of CX<sub>3</sub>−MnX and CX<sub>2</sub>═MnX<sub>2</sub>(X = H, F, Cl) Prepared in Reactions of Laser-Ablated Manganese Atoms with Halomethanes
作者:Han-Gook Cho、Lester Andrews
DOI:10.1021/om100791h
日期:2011.2.14
calculations. The Mn methylidenes have planar structures, common among early transition-metal analogues, revealing that Mn has borderline properties between the early and late transitionmetals. The computed C−Mn bond lengths of the carbene complexes in the quartet states (1.855−1.872 Å) are considerably shorter than those of the insertion complexes in the sextet states (2.057−2.120 Å), which is likely due to
Formation of carbyne complexes in reactions of laser-ablated Os atoms with halomethanes: characterization by C–H(X) and Os–H(X) stretching absorptions and computed structures
作者:Han-Gook Cho、Lester Andrews
DOI:10.1039/b811805a
日期:——
Reactions of laser-ablated Os atoms with halomethanes have been investigated. Small carbyne complexes are produced in reactions of Os atoms with fluoromethanes and identified through matrix infrared spectra and vibrational frequencies computed by density functional theory. The preference for the carbonâosmium triple bond is traced to the low energy of the Os carbyne products. The CâH and CâX stretching absorptions of the carbyne complexes are observed on the high frequency sides of the corresponding precursor bands, which result from the high s character in the CâH bond and interaction between the CâX and CâOs stretching modes, respectively. The calculated Os complex structures show a large variation with the ligands and electronic states, similar to the analogous Ru complex structures. The present report also compares previous Fe, Ru, and Os results and supports the general trend that the higher oxidation state complexes become more stable on going down the family group column.
Infrared spectra of XCIrX3 and CX2IrX2 prepared by reactions of laser-ablated iridium atoms with halomethanes
作者:Han-Gook Cho、Lester Andrews
DOI:10.1039/c002347g
日期:——
oxidation-state complexes with carbon–iridium multiple bonds are identified in the product matrix infrared spectra from reactions of laser-ablated Ir atoms with tetra-, tri- and dihalomethanes. In contrast to the previously studied Rh case, Ir carbyne complexes (XCIrX3) are generated in reactions of tetrahalomethanes, and their short Ir–C bond lengths of 1.725–1.736 Å are appropriate for the carbon–metal triple
Reactions of Thorium Atoms with Polyhalomethanes: Infrared Spectra of the CH
<sub>2</sub>
=ThX
<sub>2</sub>
, HC÷ThX
<sub>3</sub>
, and XC÷ThX
<sub>3</sub>
Molecules
作者:Jonathan T. Lyon、Lester Andrews
DOI:10.1002/ejic.200701048
日期:2008.3
and density functional theoretical calculations confirm the identity of these methylidene and methylidyne complexes. Parallels with the analogous chloromethane and Group 4 metal reaction products are discussed. Structure calculations show that the C=Th bond lengths decrease and the agostic distortion increases from CH2=ThF2 to CH2=ThFCl to CH2=ThCl2 for the methylidene complexes. The triplet-state HC÷ThF3