S-matrix theory of ionisation of polyatomic molecules in an intense laser pulse

Using the recently developed `intense-field many-body S-matrix theoryʹ we analyse the ionisation yields of polyatomic molecules in a strong laser pulse. Detailed numerical calculations are performed for the ionisation yields of a sequence of polyatomic hydrocarbons C2H2, C2H4, and C6H6. The results are found to agree well with the experimental data. It supports the hypothesis that the ionisation rate of a complex molecule does not exceed that of a single centred atomic system with comparable ionisation potential, since the amplitudes of the emitted electron from different nuclei interfere with each other that tends to reduce the total probability of ionisation.