Relativistic calculations on the ${{\rm{K}}}_{\alpha }$ x-ray satellites of platinum with multiply ionized L shell

Abstract

The energies, electric dipole rates and oscillator strengths of Kα x-ray satellites from 1s–2p transitions in platinum with a single vacancy in the K shell and variously ionized L shell are calculated using multi-configuration Dirac Fock wavefunctions with the inclusion of Breit interaction and quantum electrodynamics effects. The computations have been performed for low ionized (Pt1+–Pt6+) and also for highly ionized (Pt69+–Pt77+) Pt. As Kα x-ray satellites with spectator vacancies only in the L shell, to the best of our knowledge, have been studied for the first time, to check the accuracy of the present work, calculations have also been performed for H-, He-, Li-, Be-, B- and F-like Pt for which theoretical data for comparison exist. The purpose of choosing a high Z element is that the detailed decay properties of heavy ions due to systematic 1s–2p transitions with spectator vacancies in the L shell using fully relativistic treatment are unexplored and the increasing need for reliable data from such ions in various applications that are under investigations in recent years. Also, for heavy ions like Pt, the contribution from the competing non-radiative transitions is less and hence the atomic properties are largely due to radiative transitions. The K X ray satellite energies, rates and resonance photo- ionization cross sections from H-, He-, Li-, Be-, B- and F-like Pt are compared with available data.

K X‐ray satellite structures of bromine and molybdenum

“…Hence in this work, the convergence of the eigenfunctions, which is 10 −8 , the agreement in the length (A l ) and velocity (A v ) forms of transition rates and the comparison of K α diagram lines with the existing data are used as criteria to judge the accuracy of the present work on the variously ionized Br and Mo. Following our earlier work, [ 9 ] the assignment of the fine structure states are in LSJ notation and the initial and final configurations of Br 1+ to Br 6+ as well Mo 1+ to Mo 6+ are expressed by the holes in the respective configurations.…”

“…Following our earlier approach, [ 9 ] the correlation effect was considered by single and double (SD) excitations of electrons from the reference configurations to the virtual orbitals in the active space approximation. [ 14 ] We first generated mono‐configuration relativistic spin‐orbitals for the various initial and the corresponding final reference sets from Br 1+ to Br 5+ using Extended Optimal Level (EOL) scheme.…”

“…As the number of E1 transitions from different groups considered in this work vary from 2 to 35 leading to a closely spaced complex satellite structure, it is preferable to compute a single X‐ray energy and rate for each group of fine structure transitions so as to help in the analysis of K α L n experimental spectra. A detailed discussion in the evaluation of intensity weighted X‐ray energies and the statistically averaged transition parameters is available in earlier papers [ 9,16 ] and in this work, we describe only the necessary equations.…”

“…As systematic studies on the K α X‐ray satellite structure of medium to heavy elements are rare, the present work aims to provide a reliable data in the quantitative interpretation of experimental K α L n ( n = 0‑5) X‐ray spectra of Br and Mo. In our earlier work, [ 9 ] we had discussed and compared for the first time the K α x‐ray satellite spectra from low (Pt 1+ to Pt 6+ ) and highly ionized (H‐ to F‐like) Pt and showed that the X‐ray spectra from near‐neutral to highly ionized Pt exhibit a significant shift to higher energies due to changes in the strengths of electron–electron and electron‐nuclear interactions, while the intensities of the spectral lines deviate in general by less than 10%. The qualitative treatment of the K X‐ray satellite structure of Br and Mo is nearly the same as that of Pt, and this study is an extension of our earlier work in analyzing the K α X‐ray satellite spectra of these two atoms arising due to the decay of singly ionized 1 s shell, variously ionized 2 p shell, and other shells retaining their normal electron occupation numbers.…”