*Review* **Recent Progress in Low-Energy Electron Elastic-Collisions with Multi-Electron Atoms and Fullerene Molecules †**

**Alfred Z. Msezane \* and Zineb Felfli**

> Department of Physics and Center for Theoretical Studies of Physical Systems, Clark Atlanta University, Atlanta, GA 30314, USA; zfelfli@cau.edu

**\*** Correspondence: amsezane@cau.edu

† Professor M. Ya. *Amusia taught us not to aim at merely reproducing experimental results but at understanding the fundamental physics*.

**Abstract:** We briefly review recent applications of the Regge pole analysis to low-energy 0.0 ≤ E ≤ 10.0 eV electron elastic collisions with large multi-electron atoms and fullerene molecules. We then conclude with a demonstration of the sensitivity of the Regge pole-calculated Ramsauer–Townsend minima and shape resonances to the electronic structure and dynamics of the Bk and Cf actinide atoms, and their first time ever use as novel and rigorous validation of the recent experimental observation that identified Cf as a transitional element in the actinide series.

**Keywords:** Regge poles; generalized bound states; actinide atoms; lanthanide atoms; fullerene molecules; elastic cross sections; binding energies; Ramsauer–Townsend minima; shape resonances; electron affinities
