Multiconfiguration Dirac–Hartree–Fock energy levels, weighted oscillator strengths, transitions probabilities, lifetimes, hyperfine constants, Landé g-factors and isotope shifts of Xe LIII

ABSTRACT Accurate atomic data are essential for opacity calculations and for abundance analyses of the Sun and other stars. The aim of this work is to provide accurate and extensive results of energy levels and transition data for C i–iv. The Multiconfiguration Dirac–Hartree–Fock and relativistic configuration interaction methods were used in this work. To improve the quality of the wavefunctions and reduce the relative differences between length and velocity forms for transition data involving high Rydberg states, alternative computational strategies were employed by imposing restrictions on the electron substitutions when constructing the orbital basis for each atom and ion. Transition data, for example, weighted oscillator strengths and transition probabilities, are given for radiative electric dipole (E1) transitions involving levels up to 1s22s22p6s for C i, up to 1s22s27f for C ii, up to 1s22s7f for C iii, and up to 1s28g for C iv. Using the difference between the transition rates in length and velocity gauges as an internal validation, the average uncertainties of all presented E1 transitions are estimated to be 8.05 per cent, 7.20 per cent, 1.77 per cent, and 0.28 per cent, respectively, for C i–iv. Extensive comparisons with available experimental and theoretical results are performed and good agreement is observed for most of the transitions. In addition, the C i data were employed in a re-analysis of the solar carbon abundance. The new transition data give a line-by-line dispersion similar to the one obtained when using transition data that are typically used in stellar spectroscopic applications today.

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Ab initio predictions of the zero field splittings and the singlet–triplet transition strengths for the n → π* transition of selenoformaldehyde

Canadian Journal of Chemistry ◽

10.1139/v93-212 ◽

1993 ◽

Vol 71 (10) ◽

pp. 1706-1712 ◽

Cited By ~ 10

Author(s):

D.C. Moule ◽

L. Chantranupong ◽

R.H. Judge ◽

D.J. Clouthier

Keyword(s):

Energy Levels ◽

Random Phase ◽

Open Shell ◽

Oscillator Strengths ◽

Basis Set ◽

Zero Field ◽

Zero Field Splitting ◽

Hartree Fock ◽

Lower Valence ◽

Polarization Functions

The energy levels of the lower valence and Rydberg states of selenoformaldehyde, CH2Se, have been calculated by the SCF/CI method. Wavefunctions for the ROHF (restricted open shell Hartree–Fock) states were obtained with the Binnings–Curtis double-ζ basis set, augmented with Rydberg and polarization functions. Configuration interaction was applied to the parent configurations, PCMO (parent configuration molecular orbital). Oscillator strengths were evaluated for the allowed electric dipole transitions by the RPA (random phase approximation), and SOPPA (second-order polarization propagator approximation) methods. The spin-orbit contribution to the zero field splitting of the first triplet state, 3A2(n,π*) as well as the oscillator strengths to the three spin components were calculated by perturbation theory. These calculations predict that the Sx, Sy, and Sz components are shifted by −96.091,−96.707, and + 29.167 cm−1, respectively, from their unperturbed position. The oscillator strengths for the three components fx, fy, and fz of the 3A2(n,π*) ← 1A1(g.s.) transition were calculated to be 3.45 × 10−7, 1.15 × 10−7, and 173.0 × 10−7.

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Transition Parameters for Doubly Ionized Lanthanum

Journal of Atomic Molecular and Optical Physics ◽

10.1155/2012/246105 ◽

2012 ◽

Vol 2012 ◽

pp. 1-15 ◽

Cited By ~ 4

Author(s):

Betül Karaçoban ◽

Leyla Özdemir

Keyword(s):

Least Squares ◽

Configuration Interaction ◽

Electric Dipole ◽

Transition Probabilities ◽

Energy Levels ◽

Relativistic Effects ◽

Oscillator Strengths ◽

Least Squares Fitting ◽

Hartree Fock

The transition parameters such as the wavelengths, weighted oscillator strengths, and transition probabilities (or rates) for the nd (n=5−9)−nf (n=4−8), nd (n=5−9)−np (n=6−9), np (n=6−9)−ns (n=6−10), and ng (n=5−8)−nf (n=4−8) electric dipole (E1) transitions of doubly ionized lanthanum (La III, Z=57) have been calculated using the relativistic Hartree-Fock (HFR) method. In this method, configuration interaction and relativistic effects have been included in the computations combined with a least squares fitting of the Hamiltonian eigenvalues to the observed energy levels. We have compared the results obtained from this work with the previously available calculations and experiments in literature. We have also reported new transitions with the weighted transition probabilities greater than or equal to 105.

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Energies, Landé g-factors, and lifetimes for some excited levels of doubly ionized lanthanum

Open Physics ◽

10.2478/s11534-011-0104-6 ◽

2012 ◽

Vol 10 (1) ◽

Cited By ~ 5

Author(s):

Betül Karaçoban ◽

Leyla Özdemir

Keyword(s):

Energy Levels ◽

Hartree Fock ◽

G Factors

AbstractUsing the relativistic Hartree-Fock (HFR) method developed by Cowan, we calculated the energy levels, Landé g-factors, and lifetimes for nd (n = 5–25), ns (n = 6–24), ng (n = 5–25), nf (n = 4–22), and np (n = 6–25) excited levels of doubly ionized lanthanum (La III, Z = 57). We compared the results with previously reported calculations and experiments.

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Multiconfiguration Dirac–Hartree–Fock calculations of energy levels, wavelengths, weighted oscillator strengths, transitions probabilities and lifetimes of Cd XLVII

Zeitschrift für Naturforschung A ◽

10.1515/zna-2021-0245 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Dhia Elhak Salhi ◽

Soumaya Manai ◽

Sirine Ben Nasr ◽

Haikel Jelassi

Keyword(s):

Missing Data ◽

Quantum Electrodynamics ◽

Transition Probabilities ◽

Energy Levels ◽

Oscillator Strengths ◽

Accurate Data ◽

Cadmium Ion ◽

Hartree Fock ◽

First Time ◽

Good Agreement

Abstract Energy levels, wavelengths, weighted oscillator strengths, transition probabilities and lifetimes are calculated for all levels of 1s 2 and 1snl (n = 2–6) configurations of He-like cadmium ion (Cd XLVII). The calculations were carried out using three codes GRASP2018, FAC and AMBiT in order to provide theoretically the most accurate data. Transition probabilities are reported for all the E1, E2, M1 and M2 transitions. Breit interactions and quantum electrodynamics effects are included in the RCI calculations. Comparisons were made with other calculations and a good agreement was found which confirms the reliability of our results. We present some missing data for the He-like cadmium in this paper for the first time.

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Semiclassical perturbation Stark shifts of singly charged argon spectral lines

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stz1835 ◽

2019 ◽

Vol 488 (2) ◽

pp. 2473-2479

Author(s):

Rafik Hamdi ◽

Nabil Ben Nessib ◽

Sylvie Sahal-Bréchot ◽

Milan S Dimitrijević

Keyword(s):

Energy Levels ◽

Relativistic Correction ◽

Spectral Lines ◽

Oscillator Strengths ◽

Perturbation Approach ◽

Hartree Fock ◽

Calculated Energy ◽

Impact Approximation ◽

Singly Charged ◽

Experimental Values

AbstractUsing semiclassical perturbation approach in impact approximation, Stark shifts for singly charged argon (Ar ii) spectral lines have been calculated. Energy levels and oscillator strengths needed for this calculation were determined using Hartree–Fock method with relativistic correction (HFR). We compare our results with experimental values for 100 spectral lines. We also present results as a function of temperature for 161 spectral lines for collisions with electrons, protons, singly charged helium and singly charged argon. This work extends our previous one.

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Energies, Landé g-factors, oscillator strengths, and transition probabilities in Cs-like Pr V

Canadian Journal of Physics ◽

10.1139/cjp-2015-0308 ◽

2015 ◽

Vol 93 (12) ◽

pp. 1439-1445

Author(s):

Betül Karaçoban Usta ◽

Sevda Doğan

Keyword(s):

Electric Dipole ◽

Transition Probabilities ◽

Oscillator Strengths ◽

Hartree Fock ◽

G Factors

We have calculated relativistic energies and Landé g-factors for the levels of 5p6nf (n = 4–30), 5p6np (n = 6–30), 5p6nd (n = 5–30), 5p6ng (n = 5–30) and 5p6ns (n = 6–30) configurations and the transition parameters, such as wavelengths, oscillator strengths, and transition probabilities (or rates), for the electric dipole (E1) transitions between these levels in quadruply ionized praseodymium (Pr V, Z = 59) by using the relativistic Hartree–Fock method. We have compared the results with available calculations and experiments in the literature.

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