Temporary anion states

Aflatooni K, Hitt B, Gallup GA, Burrow PD (2001). Temporary anion states of selected amino acids. J Chem Phys 115 6489-6494. 

A second major difference between ETS and PES results from the unique properties of temporary anion states. The temporary anion states associated with the occupati YJ of un lled orbitals of most hydrocarbons have lifetimes of 10 - 10 s. Since the FVfHM resolution attainable in ETS is 0.02 - 0.05 eV, this means that the line widths due to autodetachment are generally greater than the experimental resolution. It is precisely these short lifetimes which make the study of these anions in the gas phase exceedingly difficult by optical spectroscopy and which makes electron scattering techniques ideally suited. 

Studies or reports have been made of - the temporary anion states of phosphorin, arsabenzene, and stibabenzene (P.D. Burrow et at, J- Amer. chem. Soc., 1982, 104, 425) the anomalously low basicity of phosphorin and arsabenzene (Ashe et at, ibid, 1979, 101, 1764) the ir and Raman spectra of phosphorin and arsabenzene (Ashe, G.L. Jones, and F.A. Miller, J. mol. Struct., 1982, 78. 169) the photochemical rearrangements of 1-acyloxy-1-alkoxy-X -phosphorin derivatives (M. Constenla and Dimroth, Ber., 1976, 109, 3099) the angular and energy dependence of band intensities in the photoelectron spectra of phosphorin and arsabenzene (Ashe et at, Helv., 1976, 1944) calculations of spin-orbital... 

Since the renaissance of electron scattering studies beginning in the late 1950 s, temporary anion states have been observed In all atoms and virtually all small molecules which have been examined. 

Temporary anion states may be broadly classified either as shape resonances or core-excited resonances (4). The former are well described by a configuration in which the impacting electron attaches to an atom or molecule in one of the originally unoccupied orbitals. In the latter, electron capture is accompanied by electronic excitation, giving rise to a temporary anion with a two-particle-one-hole (2p-lh) configuration. One can further distinguish core-excited resonances into those In which the resonance lies energetically below its parent state and those in which it lies above. The former are referred to as Feshbach resonances and the latter as core-excited... 

Electron transmission spectroscopy has been employed to locate the temporary anion states associated with electron capture into the empty 7t -MOs of 4//-pyran and 4-pyrone (86CPL375). 

Jordan, K. D., 8c Burrow, P. D. (1987). Temporary anion states of polyatomic hydrocarbons. Chemical Reviews, 87, 557. 

Scheer, A. M., Aflatooni, K., Gallup, G. A., Burrow, P. D. (2004). Bond breaking and temporary anion states in uracil and halouracils Implications for the DNA bases. Physical Review Letters, 92, 068102. 

A. M. Scheer, K. Aflatooni, G. A. Gallup, andP. D. Burrow, Phys. Rev. Lett., 92, 068102 1-4 (2004). Bond Breaking and Temporary Anion States in Uracil and Halouracils Implications for the DNA Bases. 

P. D. Burrow, A. E. Howard, A. R. Johnston, and K. D. Jordan, /. Phys. Chem., 96, 7570-7578 (1992). Temporary Anion States of Hydrogen Cyanide, Methyl Cyanide, and Methylene Dicyanide, Selected Cyanoethylenes, Benzonitrile, and Tetracyanoquin-odimethane. 

H.-Y. Cheng and C.-W. Chen,/. Phys. Chem. A, 115, 10113-10121 (2011). Energy and Lifetime of Temporary Anion States of Uracil by Stabilization Method. 

C.-S. Chen, T.-H. Feng, and J. S.-Y. Chao,/. Phys. Chem., 99, 8629-8632 (1995). Stabilized Koopmans Theorem Calculations on the ti Temporary Anion States of Benzene and Substituted Benzenes. 

Burrow PD, Ashe AJ III, Bellville DJ, Jordan KD (1982) Temporary anion states of phosphabenzene, arsabenzene, and stibabenzene. trends in the n and tt orbital energies. J Am Chem Soc 104 425-429... 

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