Regular Article

Topical issue

A density functional theory based comparative study of hybrid photoemissions from Cl@C₆₀, Br@C₆₀ and I@C₆₀^★

¹ Department of Natural Sciences, D.L. Hubbard Center for Innovation, Northwest Missouri State University, Maryville, MO 64468, USA
² Qatar Environment and Energy Research Institute, Hamad Bin Khalifa University, P.O. Box 34110, Doha, Qatar
³ Department of Physics and Astronomy, Georgia State University, Atlanta, GA, USA

^a e-mail: himadri@nwmissouri.edu

Received: 6 March 2020
Accepted: 21 July 2020 Received in final form: 15 July 2020

Published online: 22 September 2020

Abstract

Photoionization from atom-C₆₀ hybrid levels in halogen endufullerene molecules, Cl@C₆₀, Br@C₆₀ and I@C₆₀, is calculated using a linear response density functional method. Both the ordinary electron-configuration where the open shell halogen is at the center of C₆₀ and the stable configuration after the atom receives an electron from C₆₀ to form a closed shell anion are considered. Similar ground state hybridization is found for all three systems while, in general, a slight weakening of the effect is noticed after the electron transfer. At lower photon energies, cross sections of the outer hybrid levels attain identical shapes from enhancements driven by the C₆₀ plasmon resonances, while the higher energy emissions remain distinguishable from the differences in atomic responses. These results further show near insensitivity to the choice of a configuration. The inner hybrid cross sections in general exhibit similar overall structures, although differ in details between molecules. However, for these states the results significantly differ before and after the electron transfer – a feature that can be useful to experimentally determine the real configuration of the molecules via photoelectron spectroscopy.