Interference effects on (e, 2e) electron momentum profiles: a comparative study for CCl4 and CF4*
Institute of Multidisciplinary Research for Advanced
Materials, Tohoku University, 980-8577
Received in final form: 30 September 2016
Published online: 22 December 2016
Interference effects on electron momentum density distributions have been studied using electron momentum spectroscopy (EMS) for the three outermost orbitals of CCl4, which are constructed from the Cl 3p nonbonding atomic orbitals. The EMS experiment was conducted in the symmetric noncoplanar geometry at an incident electron energy of 2.0 keV. Interference pattern has then been obtained by dividing the experimental data by distorted-wave-Born-approximation cross section for an isolated Cl 3p atomic orbital. A comparison with the result of our earlier study on CF4 [N. Watanabe, X.-J. Chen, M. Takahashi, Phys. Rev. Lett. 108, 173201 (2012)] has demonstrated that the period of the interference pattern reflects the internuclear distance between the constituent halogen atoms. Furthermore, the present result strongly suggests that distorted-wave effects lead to partial destruction of the interference for CCl4 at large momentum.
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag 2016