Coulomb explosion in aromatic molecules and their deuterated derivatives

Coulomb explosion within some aromatic molecules (furan, pyrrole, pyridine and pyrazine) and their deuterated derivatives induced by strong fs laser fields (∼4×1016 W/cm2) is studied at λ=790 nm by means of time-of-flight (TOF) mass spectrometry. It is found that in hydrogenated molecules the Coulomb explosion process begins at internuclear distances about twice larger than the equilibrium distance (Re), while the expansion of the molecular skeleton in the deuterated derivatives is smaller. Based on the estimated kinetic energy values of the fragment ions, the charge distribution in the transient molecular species is also discussed.