ISSN:
1089-7690
Source:
AIP Digital Archive
Topics:
Physics
,
Chemistry and Pharmacology
Notes:
Electron photodetachment spectra of two complex anions, C6H5CH2OHF− and CH3OHOCH−3, have been recorded, using an ion cyclotron resonance spectrometer to generate, store, and detect the ions. The threshold energies determine the potential well depths of the ion–molecule reactions for which the anions are presumable intermediates. The detachment energies for C6H5CH2OHF− and CH3OHOCH−3 are ≤3.05±0.06 and 2.26±0.08 eV, respectively. The ability to measure absolute photodetachment cross sections is demonstrated in the latter case. The electron affinity of C6H5CH2O is 2.14±0.02 eV (49.3±0.5 kcal/mol). One would predict that complex ions of the form ROHF− where ROH is less acidic than HF would have poor Franck–Condon factors for adiabatic threshold photodetachment. This prediction is confirmed; five such ions display cross sections smaller than about 10−20 cm2 at all wavelengths above 365 nm. A useful correlation between ion structure and observation or nonobservation of visible/near-UV photodetachment is therefore demonstrated.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.452560
