PHOTO-DISSOCIATION AND PHOTODETACHMENT OF CL2-, CLO-, CL3- AND BRCL2-

Absolute cross sections for the photodestruction of CI2, CIO-, CI3 -, and BrCI2 - were measured over the wavelength range of 3500-7600 A using a drift tube mass spectrometer-laser apparatus. The photodissociation cross section for CI 2 - has two bands, as has been observed for the isoelectronic Ar2 + ion. The wavelength dependence of these bands is used to adjust the calculated potential curves of the ion in the Franck-Condon region. The photodestruction cross section for CIO- has a narrow band peaked at 4300 Å with a width of 400 Å, superimposed on a continuum that slowly increases with photon energy. The narrow band is attributed to photodissociation and the continuum to photodetachment. CI 3 - and BrCI2 - have no significiant photodestruction cross sections for wavelengths longer than 4700 Å. At shorter wavelengths, the cross sections increase with increasing photon energy. The photodestruction of these ions is attributed to photodissociation. The present gas phase measurements are compared with optical spectra for the ions obtained in different environments. © 1979 American Institute of Physics.