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Published on: July 27, 2018
Circular dichroism in photoionization of H2
D Dowek1, J F Pérez-Torres, Y J Picard
1Institut des Sciences Moléculaires d'Orsay (FRE 3363 Université Paris-Sud et CNRS), Bat 350, Université Paris-Sud, 91405 Orsay Cedex, France.
Abstract:
Circular dichroism is a consequence of chirality. However, nonchiral molecules can also exhibit it when the measurement itself introduces chirality, e.g., when measuring molecular-frame photoelectron angular distributions. The few such experiments performed on homonuclear diatomic molecules show that, as expected, circular dichroism vanishes when the molecular-frame photoelectron angular distributions are integrated over the polar electron emission angle. Here we show that this is not the case in resonant dissociative ionization of H2 for photons of 30-35 eV, which is the consequence of the delayed ionization from molecular doubly excited states into ionic states of different inversion symmetry.
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