Double photoionization spectra of 3,4-dibromothiophene has also been investigated by coincidence spectroscopy technique based on electron time-of-flight measurement.It was used in the preparation of thieno[3,4-b]thiophene. It was aslo used as starting material in the synthesis of alkyl substituted, fused thiophenes. Double photoionization spectra of 3,4-dibromothiophene has also been investigated by coincidence spectroscopy technique based on electron time-of-flight measurement. It was used in the preparation of thieno[3,4-b]thiophene. It was aslo used as starting material in the synthesis of alkyl substituted, fused thiophenes.