Show simple item record

dc.creatorCosby, P. C.en_US
dc.creatorHeidrich, J. L.en_US
dc.creatorMoseley, J. T.en_US
dc.descriptionAuthor Institution: Molecular Physics Center Stanford Research Instituteen_US
dc.description.abstractPhotodissociation of thermal $CO^{-}_{3}$ to produce $O^{-} +CO_{2}$ has been observed throughout the wavelength range of 6390 -- 5640 {\AA} using a tunable dye laser with a resolution of 0.5 {\AA} and a drift tube mass spectrometer. The photodissociation cross section has significant structure over this photon energy range. Between 6390 and 6050 A there are six well-defined peaks, plus an additional three peaks which are found by a simple deconvolution. These peaks have a FWHM of about 77 cm$^{-1}$ and a mean separation of about 100 cm$^{-1}$. At least nine other peaks are spaced irregularly between 6050 and 5640 \AA. The photodissociation cross section varies from 0.4 to 3.3 $\times$ 10$^{-18}$ cm$^{2}$ over the wavelength range observed. The absolute magnitude and the wavelength dependence of the cross section are independent of photon intensity and gas pressure, indicating a single photon process which involves no collisional dissociation. We do not yet have a full explanation for the detailed structure of the cross section. However, it is almost certainly related to a bound metastable excited state of $CO_{3}^{-}$ which dissociates rapidly either through a curve crossing to a dissociating state, or by a change in geometry brought about by vibration which leads to an unstable configuration. The envelope centered at 6200 {\AA} is probably related to the $\nu$$_{3}$ or $\nu$$_{4}$ bending modes of the excited $CO_{3}^{-}$. We expect to extend these measurements to longer and shorter wavelengths in the near future, and to investigate other ions.en_US
dc.format.extent166909 bytes
dc.publisherOhio State Universityen_US

Files in this item


Items in Knowledge Bank are protected by copyright, with all rights reserved, unless otherwise indicated.

This item appears in the following Collection(s)

Show simple item record