Home > Seminars > Année 2016 > Séminaire de Saikat NANDI (13 déc. 2016)
Séminaire de Saikat NANDI (13 déc. 2016)
Lund University, Atomic Physics Division, Lund, Sweden
by - 1 December 2016
Probing wave-particle duality in photoionization of polyatomic molecules
Coherent superposition of quantum objects (electrons) from spatially separated nucleon centers leading to the well-known Young-type interference pattern has been observed unambiguously for photoionization of H2 and core-ionization of N2. Similarly, following ionization from a core molecular orbital the wave associated with the ionized electron often gets partially scattered in the surrounding molecular potential, which then interferes with the initial wave giving rise to diffraction effects. However, for electron emission from a delocalized molecular orbital both phenomena can co-exist and it becomes hard to differentiate the two. An efficient method to study these effects can be studying the cross section ratios of different vibrational levels (“v-ratios”) in the same electronic state of the molecule under investigation. According to the Franck-Condon principle, in absence of any diffraction or interference effect (as well as any shape-resonance), the v-ratios should essentially be an energy independent constant. However, a significant departure from the Franck-Condon values has been noted in the photon energy dependence of the v-ratios in cases of di- and polyatomic molecules.
In this talk, we will elaborate some new results showcasing the diffraction and interference effects for inner-valence photoionization of CH4 molecule and valence photoionization of CO2 molecule and how that fits into the overall research activities.
Séminaire de Saikat NANDI - 128.3 KiB 13 décembre 2016 |