Gas phase electron resonance spectra

Gas chromatography and mass spectroscopy (GC/MS) of inorganic and organometallic compounds, 18 273-276 Gaseous hydroxides, 5 215-258 dimerization of, 5 224 mass spectrometric study of, 5 220-225 metalic, 5 220 nonmetallic, 5 217-220 study of in oxyhydrogen flame, 5 225-226 types of, 5 215-217 Gases, see also specific substances high ternperamre species from, 14 137-139 thermal decomposition of, 17 90-93 Gas phase electron resonance spectra, of sulfur and selenium fluorides, 24 190... 

The electronic states and levels (T ) are taken from the recent compilation of Barrow (5). His results were derived from the spectral measurements of Di Lonardo and Trombetti (4). Further confirmation that the ground state is inverted is provided by the results of an analysis of the gas-phase electron resonance spectra by Carrington et al. ( ). The rotational constant (B ) is calculated from the microwave data (B ) of Amano and Hirota (7). Other values for B determined from EPR 22 ... 

The determinable parameters from gas-phase electron resonance spectra are functions of combinations of these constants, and in general it is not possible to obtain unique values of a, b, c and d from the experimental data. Where possible, we have quoted values of the empirical parameters 4, and A, as defined by Radford, for the hyperfine interaction constants of gas-phase radicals. These parameters appear in the expressions... 

Graham et al. (416) have concluded that the ground state is linear 2E on the basis of electron spin resonance of C2H in solid matrices. The absorption spectra in the gas phase have apparently not been observed. Graham et al. (416) have seen two weak absorption bands at about 3300 and 10,000 A in solid Ar and have assigned the former to a B2A <- X2L transition and the latter to an A2W - X2Z transition. However, Gilra (398a) believes that the 10,000 A transition is part of the C2 Phillips system. D0(C2—H) = 5.33 0.05 eV. 

Prereactive behaviors were identified very early and an impressive series of examples was listed in a book by Klabunde in 1980 [266]. Electron spin resonance (ESR) studies reveal that in low-temperature matrices electron-transfer reactions are blocked as a rule and most, if not all, charge-transfer complexes involved in standard gas-phase harpoon reactions have been stabilized and observed in matrices. The ESR spectra of these systems revealed nearly complete electron transfer. Similar conclusions have also been drawn from infrared spectroscopy. For example, outside the field of alkali metal atoms, evidence of an AHNO complex has been obtained by this technique [267]. It should not be thought that every metal atom is able to make charge transfer with every molecule. For example, no indication exists of a charge transfer between Cu and NO in an argon matrix [268]. 

Intermediate species in the gas phase may also be studied by electron resonance methods, although the spectra obtained are usually more complex than those observed with condensed phases. In small gaseous radicals and atoms with degenerate orbital states, the orbital angular momentum will not be quenched, and may make a contribution to the paramagnetism of the species. Even in orbitally non-degener-... 

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