Constructing Electron-Atom Elastic Scattering Potentials Using Relativistic Coupled-Cluster Theory: A Few Case Studies

Abstract

In light of the immense interest in understanding the impact of an electron on atoms in the low-energy scattering phenomena observed in laboratories and astrophysical processes, we propose an approach to construct potentials using relativistic coupled-cluster (RCC) theory for the determination of electron-atom (e-A) elastic scattering cross-sections (eSCs). The net potential of an electron, scattered elastically by an atom, is conveniently expressed as the sum of the static (Vst) and exchange (Vex) potentials due to interactions of the scattered electron with the electrons of the atom and potentials due to polarization effects (Vpol) on the scattered electron by the atomic electrons. The Vst and Vex potentials for the e-A eSC problems can be constructed with a knowledge of the electron density function of the atom, while the Vpol potential can be obtained using the polarizabilities of the atom. In this paper, we present the electron densities and electric polarizabilties of Be, Mg, Ne and Ar atoms using two variants of the RCC method. Using these quantities, we construct potentials for e-A eSC problems. To obtain Vpol accurately, we evaluate the second- and third-order electric dipole and quadrupole polarizabilities using a linear response approach.