The experimental electronic and vibrational spectra of fulvene

Abstract

The infrared spectrum of fulvene has been observed from 250 to 4000 cm-1 in the gas phase, and as a glass and a polycrystalline layer at liquid nitrogen temperature. On the basis of gas-phase contours and P-R separations 14 of the 30 fundamental vibrations have been assigned. The electronic absorption spectrum of fulvene has been recorded from 400 to 167 nm in the gas phase and four electronic transitions have been identified. The lowest-energy transition was found to be broad and structureless while the three higher-energy transitions showed an extensive vibrational fine structure. The electronic transitions have been tentatively assigned on the basis of VESCF-MO calculations and a partial analysis of the vibronic structure has bees made.