Resonant two-photon ionization spectra of p-difluorobenzene mixed van der Waals complexes

Van der Waals heterodimers of p-difluorobenzene (DFB) with other molecules, prepared in a supersonic jet beam expansion, were studied by resonant two-photon ionization (R2PI) through their S1 ← S0 transition. The functional molecule in these systems is DFB. The partners-molecules are: p-difluorobenzene (homodimer), fluorobenzene, 1,3,5-trifluorobenzene, furan, N-methylpyrrole, ethanol and propargyl alcohol. In each case, the recorded spectra are relatively broad as the result of at least two structures present in the molecular beam. Using hexafluorobenzene or pyrrole as partners of DFB, the S1 ← S0 transition of the respective heterodimer was not detected. Intracluster ion-molecule reactions have been observed in the cases of p-difluorobenzene with ethanol and propargyl alcohol.