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

Using the recently developed 'intense-field many-body S-matrix theory' wt a nalyse the ionisation yields of polyatomic molecules in a strong laser puls e. Detailed numerical calculations are performed for the ionisation yields of a sequence of polyatomic hydrocarbons C2H2, C2H4, and C6H6 The results a re found to agree well with the experimental data. It supports the hypothes is that the ionisation rate of a complex molecule does not exceed that of a single centred atomic system with comparable ionisation potential, since t he amplitudes of the emitted electron from different nuclei interfere with each other that tends to reduce the total probability of ionisation. (C) 20 01 Elsevier Science B.V. All rights reserved.