The absorption spectra of hexatriene and divinyl acetylene in the vacuum ultra-violet

Abstract

The absorption spectra of hexatriene and divinyl acetylene have been investigated in the region 2700-1200 A. In both molecules the longest wave-length regions of absorption are the strongest and these are interpreted as N → V 1 intravalence shell transitions. The spectra appear to be consistent with a value of about 8·2 V for the first ionization potential of hexatriene. Calculations based oh certain features of the spectra give reasonable values for the double-bond resonance integral. Graphs are given which enable the first regions of absorption and the ionization potentials of the higher polyenes to be predicted.