We have developed relativistic coupled-cluster (RCC) theory to study elastic scattering of electrons from free and confined Ca atoms. For this purpose, we first investigated electron correlation effects on the atomic properties of the Ca atom trapped inside an attractive spherically symmetric potential well of an endohedral fullerene C60 cluster and obtained electron correlation energy, ionization potential and dipole polarizability of this atom. Our results are compared with the reported calculations employing multi-configuration Hartree–Fock (MCHF) method. We found that trends in correlation energy with respect to the potential depth are the same, but magnitudes are very large in the relativistic calculations. Finally, using the obtained charge density and phase shift analysis technique we determined the differential and total cross-sections for elastic scattering of electrons from free and confined Ca atoms and demonstrated the role of potential depth in these properties.

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Electron impact excitation of Ge-like (Xe22+) to Cu-like (Xe25+) highly charged xenon ions are studied and dipole allowed fine-structure transitions in the wavelength range 9–25 nm are considered. We use relativistic distorted wave method to calculate the electron excitation cross sections for the different transitions of the four ions in the scattered electron energy range from excitation threshold to 1500 eV. The ionic bound state wavefunctions have been obtained using multi-configuration Dirac–Fock method. To ascertain the accuracy of the wavefunctions, the wavelengths and oscillator strengths of the considered transitions in these ions are calculated and compared with the previously reported measurements and other theoretical calculations, where available. For plasma diagnostic applications, the obtained cross sections are further used to calculate the rate coefficients of the transitions as well as fitted with an analytical expression which can be used in plasma model conveniently.

We study electron impact excitation of In + using relativistic distorted wave method and report cross sections for 37 transitions among the fine-structure levels of 5s 2 , 5s5p, 5s5d, 5s6s and 5s6p configurations at the scattered electron energies upto 200 eV. The bound state wavefunctions of the target ion are obtained within multi-configuration Dirac-Fock approach. Our calculated oscillator strengths are compared with the results from the NIST database and other theoretical calculations. Cross sections are fitted with an analytical formula and the fitting parameters are made available for their possible applications in plasma modeling.

Synopsis A systematic study of electron impact excitation of Ge-like highly charged xenon ions have been carried out in Extreme Ultraviolet (EUV) range within fully relativistic multiconfiguration Dirac-Fock framework. The cross section calculation reported here are performed for dipole allowed transitions for Xe22+ ions from ground state 4s24p2 to 4s24p3 and 4s24p4d excited fine structure levels. The analytic fitting for the cross section data for incident electron energy range within 50 to 1500 eV have been provided for further applications in various plasma diagnostic techniques.