VUV-optical oscillator strength distributions of C2H6O and C3H8O isomers

Abstract

The photoabsorption cross sections of C2H6O isomers (ethyl alcohol and dimethyl ether) and C3H8O isomers (n-propyl alcohol, isopropyl alcohol, and ethyl methyl ether) have been measured in the wavelength region from 30 nm to the ionization potential of each molecule (about 120–130 nm) using an ionization chamber. The obtained photoabsorption cross sections show a maximum value at about 70–80 nm for each molecule. In the wavelength region shorter than about 50 nm, the cross sections are almost the same among isomers and equal to the sum of the cross sections for the constituent atoms. In the longer wavelength region, however, the cross sections show different peaks and shoulders depending on its molecular structure. Especially in the cases of dimethyl ether and ethyl methyl ether vibrational structures of the cross section are observed in the wavelength region from 70 to 100 nm.