Kermit C. Smyth

Photodetachment of electrons from phosphide ion - The electron affinity of PH2.

The relative cross section for photodetachment of electrons from PH2− has been measured in the wavelength region 725–1020 nm (1.71–1.22 eV). An ion cyclotron resonance spectrometer has been used to generate, trap, and detect the negative ions, while two light sources have been employed to study photo‐detachment: a 1000‐W xenon arc lamp with grating monochromator and a continuously tunable laser. A single sharp threshold in the cross‐section curve has been observed, and a detailed analysis has yielded a value for the electron affinity, E.A. (PH 2·) = 1.25 ± 0.03 eV.

Photodetachment of an electron from selenide ion - The electron affinity and spin-orbit coupling constant for SeH.

The relative cross section for the gas phase photodetachment of an electron from SeH− has been determined in the wavelength region 428–578 nm (2.90–2.15 eV). An ion cyclotron resonance spectrometer was used to generate, trap, and detect the negative ions, and a 1000‐W xenon arc lamp with a grating monochromator was employed as the light source. The cross section exhibits two sharp thresholds, whose positions remain unchanged for the photodetachment of SeD−. As a result, the electron affinity and the spin‐orbit coupling constant have been evaluated: E. A. (SeH·)=2.21± 0.03 eV and A (SeH·)=−1815± 100 cm−1.

Photodetachment of negative ions using a continuously tunable laser and an ion cyclotron resonance spectrometer

Negative ions photodetachment by continuously tunable laser and ion cyclotron resonance spectrometer