Alkanes spectroscopy

Infrared radiation, electromagnetic spectrum and, 419, 422 energy of. 422 frequencies of, 422 wavelengths of, 422 Infrared spectroscopy, 422-431 acid anhydrides, 822-823 acid chlorides, 822-823 alcohols. 428, 632-633 aldehydes, 428. 730-731 alkanes, 426-427 alkenes, 427 alkynes, 427 amides. 822-823 amines, 428, 952 ammonium salts, 952-953 aromatic compound, 427-428, 534 bond stretching in, 422... 

Spectroscopy of the PES for reactions of transition metal (M ) and metal oxide cations (MO ) is particularly interesting due to their rich and complex chemistry. Transition metal M+ can activate C—H bonds in hydrocarbons, including methane, and activate C—C bonds in alkanes [18-20] MO are excellent (and often selective) oxidants, capable of converting methane to methanol [21] and benzene to phenol [22-24]. Transition metal cations tend to be more reactive than the neutrals for two general reasons. First, most neutral transition metal atoms have a ground electronic state, and this... 

The reaction can be easily monitored by IR spectroscopy since surface silanols give a characteristic peak at 3747 cm hi order to establish the mass balance, it is necessary to obtain an elemental analysis of the solid (M, C, H, N. ..) and to measure the amoimt of alkane evolved Wing grafting. 

Propyhdyne formed from propene on lr4 supported on y-Al203 was observed by IR and NMR spectroscopies [38]. When ethene or propene was brought in contact with oxide-supported lr4 [39,40], Ire [39,40], or Rhe (A.M. Argo and B.C. Gates BC, impubhshed results) in the presence of H2, hydrocarbon hgands were formed (namely, alkyls and /r-bonded alkenes), which have been inferred from IR spectra to be intermediates in hydrogenation to make alkanes, as discussed later. The population of these hydrocarbon ligands on the supported clusters depends sensitively on the conditions, such as reactant partial pressures and temperature. 

Greiner, N.R. (1970) Hydroxyl radical kinetics by kinetic spectroscopy. VI. Reactions with alkanes in the range 300-500 K. J. Chem. Phys. 53, 1070-1076. 

Apart from the more conventional transport measurements of molecular junctions at constant bias voltage, alkane(di)thiols-based molecular junctions were also characterized by transition voltage spectroscopy [258, 259], AC voltage modulation [260], and inelastic electron tunneling spectroscopies [261],... 

The theoretical and experimental principles of PE spectroscopy have been reviewed extensively7-10. In particular, the reader is referred to the chapter The Photoelectron Spectra of Saturated Hydrocarbons in the volume The Chemistry of Alkanes and Cycloalkanes of the present series11. Consequently we shall limit ourselves to the essentials needed for following the arguments presented in this chapter. 

The correct analysis of the homologous ion series has certain limitations. Low abundances of peaks in some series require the attention and experience of a researcher. Usually alkane series are dominated in the mass spectra of the most various compounds. Fragmentation initiated by one functional group may completely suppress or notably camouflage other reactions of polyfunctional substances. In the latter case it is useful to consider IR-spectroscopy data in mass spectral interpretation. 

The paramagnetic oxygen ions 0 , 01> and 0J have been formed on magnesium oxide and studied by EPR spectroscopy. The reactivity of these ions with hydrocarbons follows the sequence 0 >>03> >02. Both with alkanes and alkenes the initial reaction is thought to be hydrogen atom abstraction. 

Ozin GA, Flugues F, Mattar SM, McIntosh DF (1983) Low nuclearity silver clusters in faujasite-type zeolites optical spectroscopy, photochemistry and relationship to the photodimerization of alkanes. J Phys Chem 87 3445-3450... 

One of the initial spectroscopic methods applied to stationary-phase characterization was Fourier transform infrared spectroscopy (FTIR). This originated from several important studies of phase conformational order in crystalline n-alkanes conducted in the late 1960s and early 1980s by Snyder, Maroncelli, and coworkers [111-114], In this work, assignments of C—H bond wagging modes were associated with chain... 

In situ infrared (IR) spectroscopy and calorimetry were used by the Lercher group during alkane adsorption measurements by gravimetry for various zeoHtes [5, 14]. IR spectra of the OH-streching vibrations of Bronsted acid sites in Ferrierite during adsorption of n-butane at 333°K are illustrated in Figure 13.7. 

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