ELECTRONIC-SPECTRUM OF THE DIACETYLENE RADICAL CATION IN SOLID RARE-GASES

The matrix isolation and laser induced fluorescence techniques are applied to the study of the electronic spectrum of C4H2 + and its deuterated varieties. The ion is produced in solid Ne in several distinct sites by VUV photoionization of the parent diacetylene. The major site shows a vibronically well resolved X2II g→A2IIu fluorescence spectrum. Comparison of the fundamental frequencies with the gas phase values shows in most cases negligible perturbation by the solid medium (< 0.05%). Study of the fluorescence excitation spectra provides new information about the upper state vibrational potential function. © 1979 American Institute of Physics.