Regular Article

Interchannel mixing in the K-shell photoionization of CH₄^⋆

¹ Institute of Physics, Southern Federal University, 344090 Rostov-on-Don, Russia
² Rostov State Transport University, 344038 Rostov-on-Don, Russia
³ Institute of Physics and Center for Interdisciplinary Nanostructure Science and Technology (CINSaT), University of Kassel, D-34132 Kassel, Germany

^a e-mail: e-mail: novnim@mail.ru
^b e-mail: e-mail: vlsu16@mail.ru

Received: 8 October 2018
Received in final form: 22 January 2019
Published online: 17 April 2019

Abstract

Rearrangement of the electron shells accompanying inner-shell photoionization of the CH₄ molecule is studied theoretically. For this purpose, the K-shell photoionization cross section σ_1s (ω) and the respective photoelectron angular distribution (PAD) parameter β^e_1s(ω) are computed in different approximations using the single center method. It is obtained that a strong mixing of the partial ionization channels in the vicinity of the 1s ionization threshold, caused by the the non-spherical part of the molecular potential, results in a qualitative difference between the electronic rearrangement effects in molecules, as compared to atoms.