Photodetachment spectrum

Figure 5. The photodetachment spectra of Az measured by the photodetachment-modulated electron capture detector (PDM-ECD) in 10% argon-in-methane buffer gas at three different temperatures.

Electron photodetachment upon laser excitation of the solvent anion above 1.76 eV was observed (Fig. 2a,c) [18]. The cross section of photodetachment linearly increases between 1.76 and 3 eV (Fig. 2b). Under the same physical conditions, the photodetachment and absorption spectra of the solvent anion are identical (Fig. 2b) [20], suggesting a bound-to-CB transition the quantum yield of the photodetachment is close to unity. The photodetachment spectrum is similar to the photoelectron spectra of (C02) 9 clusters observed by Tsukuda et al. [24] in the gas phase it is distinctly different from the electron photodetachment spectra of CO2 in hydrocarbon liquids [27]. This suggests that a C-C bound, 7)2, symmetric dimer anion constitutes the core of the solvent radical anion [18,19]. 

Electron photodetachment spectra for indenyl and fluorenyl anions have been measured and the electron affinities of the corresponding radical and bond dissociation energies of the corresponding neutrals determined. Comparison has been made with solution-phase data in an attempt to determine the dependence of gas and solution properties on ionic size and extent of charge distribution.3 Benzocyclopropenyl anion... 

T. Takayanagi, A. Wada, Quantum reactive scattering calculations of photodetachment spectra of the FHD- anion, Chem. Phys. Lett. 348 (2001) 514. 

Schatz, G.C. (1990). Quantum theory of photodetachment spectra of transition states, J. Phys. Chem. 94, 6157-6164. 

Figure 8 Photodetachment spectra of [CuPc(S03)4] at (a) 266 rnn and (b) 193nm and of [CuPc(S03)4] at (c) 266 nm and (d) 193nm. (Reprinted by permission from Macmillan Publishers Ltd Nature, Wang and Wang, 1999)...

Ion-beam photodetachment spectrometer used to measure high-resolution photodetachment spectra and autodetachment of C2 ions Laser optogalvanic spectroscopy used to determine photodetachment threshold for CN ... 

Branscomb (1 ) deduced from his photodetachment spectra that B and r are very close to the values for 0H(g). Our... 

Sowada and Holroyd have used a combined A -ray-visible-dye-laser doublepulse technique to determine the photodetachment spectra of the anions of biphenyl, trans-siWhene, pyrene, perylene, benzperylene, coronene, and nitrobenzene in non-polar solvents. 

We have already mentioned the interpretation of photodetachment spectra of FH2 and XHX (X = Cl, Br, I), in terms of quantized transition state resonances. Similar experiments have been carried out for IDF, OHF , OHC1, OHOH , and HOHOH (174-177), and these experiments have been interpreted in terms of resonances and other types of vibration-rotation energy level structure associated with the transition state species of the neutral product (10,11,17-19,162,163,174-178). The FH2 and FD " photodetachment experiments provide a particularly striking example of the observation of quantized transition states in experimental spectra (133-135). In theoretical work carried out to analyze recent experimental work on photodetachment, in particular for OHC1 (176), the calculated cumulative reaction probability for the O + HC1 reaction showed steps at quantized hindered rotor energies (as well as sharper resonances due to trapped states), but the steps had transmission coefficients considerably smaller than unity. 

J. D. Kress and E. F. Hayes, Assignment of peaks in photodetachment spectra using predicted densities of reactive states Applications to H2F and D2F, J. Chem. Phys. 97 4881 (1992). 

Figure 24.32 FHJ photodetachment spectra. Both pora-FH and normal FHj cases are shown, together with theoretical calculations. The peak structure was demonstrated to correspond to the bending motion in the transition-state region of neutral FH2. Adapted from ManoLopoulos et al. Science, 1993, 262 1852, with permission of AAAS...

The photodissociation on coupled potential surfaces of H2S has also been treated in Ref. 40 and a similarly good agreement (with the reference data of Simah et alJ ) has been obtained. As applications of the concept of regularized diabatic states we mention work on Rydberg emission spectra of and on photodetachment spectra of N02. While the diabati-... 

Fig. 1. Comparison of experimental and theoretical photodetachment spectra of N02. The zero of the energy scale corresponds to the minimum of the X Ai potential energy surface of NO2. Only the higher-energy band corresponding to the state...

V. Bonacic-Koutecky, L. Cespiva, P. Fantucci, J. Pittner, and J. Koutecky, Effective Core Potential-Configuration Interaction Study of Electronic Structure and Geometry of Small Anionic Agn Clusters Predictions and Interpretation of Photodetachment Spectra , J. Chem. Phys. 100, 490 (1994). 

Rotational analysis of photodetachment spectra of H2CCHO and D2CCDO. ... 

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