VUV electronic state spectroscopy of 1,1-difluoroethene and difluorochloromethane by high resolution synchrotron radiation

Abstract

High resolution VUV photoabsorption spectra of 1,1-difluoroethene (C₂H₂F₂) and difluorochloromethane (CF₂HCl) are reported in the wavelength range 115–200 nm (10.8–6.2 eV). New photoabsorption features are observed in C₂H₂F₂ and some Rydberg and vibrational assignments are proposed for the first time. Evidence for a weak vibrational pattern in CF₂HCl is discussed here for the first time. Absolute cross section values have been obtained allowing photolysis lifetimes to be derived in the Earth’s troposphere and stratosphere.