Triple-differential cross section for the twisted-electron-impact ionization of the water molecule

In this paper, we present the results of the triple differential cross section (TDCS) for the (e, 2e) process on H2O molecule for the plane wave and the twisted electron beam impact. The formalism is developed in the first Born approximation. We describe the plane or twisted wave, plane wave, the linear combination of atomic orbitals (LCAO) (self-consistent field LCAO method), and Coulomb wave for the incident electron, scattered electron, the molecular state of H2O, and the ejected electron, respectively. We investigate the angular profiles of the TDCS for the outer orbitals 1b(1), 3a(1), 1b(2), and 2a(1) of the water molecule. We compare the angular profiles of the TDCS for the different values of orbital angular momentum (OAM) number m of the twisted electron beam with that of the plane wave beam. We also study the TDCS for macroscopic H2O target to explore the effect of opening angle theta(p) of the twisted electron beam on the TDCS. Our results clearly show the effect of the twisted electron's OAM number (m) and the opening angle theta(p) on the TDCS of the water molecule.