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1.
Weighted oscillator strengths, weighted radiative rates, and line strengths for all the E1 transitions between 285 fine-structure levels belonging to the 3d6, 3d54s, and 3d54p configurations of Fe III are presented, in ascending order of wavelength. Calculations have been undertaken using the general configuration interaction (CI) code CIV3. The large configuration set is constructed by allowing single and double replacements from any of 3d6, 3d54s, 3d54p, and 3d54d configurations to nl orbitals with n?5,l?3 as well as 6p. Additional selective promotions from 3s and 3p subshells are also included in the CI expansions to incorporate the important correlation effects in the n=3 shell. Results of some strong transitions between levels of 3d6, 3d54s, and 3d54p configurations are also presented and compared with other available calculations. It is found that large disagreements occur in many transitions among the existing calculations.  相似文献   

2.
The ab initio   quasirelativistic Hartree–Fock method developed specifically for the calculation of spectral parameters of heavy atoms and highly charged ions is used to derive transition data for a multicharged tungsten ion. The configuration interaction method is applied to include electron correlation effects. The relativistic effects are taken into account in the Breit–Pauli approximation for quasirelativistic Hartree–Fock radial orbitals. The energy level spectra, radiative lifetimes and Lande gg-factors are calculated for the 4p64d2, 4p64d4f, and 4p54d3 configurations of the ion W36+. The transition wavelengths, spontaneous transition probabilities, oscillator strengths, and line strengths for the electric dipole, electric quadrupole, electric octupole, and magnetic dipole transitions among the levels of these configurations are tabulated.  相似文献   

3.
The ab initio quasirelativistic Hartree-Fock method developed specifically for the calculation of spectral parameters of heavy atoms and highly charged ions was applied to determine atomic data for tungsten ions. The correlation effects were included by adopting the configuration interaction method. The Breit-Pauli approximation for quasirelativistic Hartree-Fock radial orbitals was employed to take into account relativistic effects. The energy level spectra, radiative lifetimes, Lande factors g were calculated for the 4p64d, 4p64f and 4p54d2 configurations of W37+ ion. The atomic data, namely, the transition wavelengths, spontaneous emission rates and oscillator strengths for the electric dipole, electric quadrupole and magnetic dipole transitions among and within the levels of these configurations are tabulated.  相似文献   

4.
We present accurate oscillator strengths, line strengths and radiative rates for 1073 E1 transitions among the 86 levels belonging to 2s22p4, 2s2p5, 2p6, and 2s22p3(4So, 2Do, 2Po)3? configurations in Mg V. We have used 1s and 2s Hartree-Fock orbitals, re-optimized 2p on 2p3(2Do)3s 3Do and optimized 3s,3p,3d orbitals on real states. Sixteen additional orbitals up to 8d are optimized either as a correction to n = 3 physical orbitals or as a correlation orbital. A very large set of configurations including up to three electron promotions are used to account for all important correlation effects. All of the main five terms in the Breit-Pauli operator (except the orbit-orbit interaction) are included in order to account for the relativistic effects. Small adjustments to the diagonal elements of the Hamiltonian matrix are made to bring the calculated energies within a few cm−1 of the corresponding NIST recommended data wherever available. The calculated oscillator strengths, line strengths, and radiative rates for almost all of the E1 transitions show excellent agreement with the corresponding MCDF results of Fischer. The recent results of Bhatia et al. are found to be consistently higher by 20-45%. The accuracy of the present calculation is considered to be better than the NIST accuracy ratings for various transitions.  相似文献   

5.
Non-orthogonal orbitals in the multiconfiguration Hartree-Fock approach are used to calculate line strengths, oscillator strengths and transition probabilities for E1 transitions among the fine-structure levels of the 3s23p3, 3s3p4, 3s23p23d, 3s3p33d, 3p5 and 3s23p3d2 configurations in Fe XII and 3s23p, 3s3p2, 3s23d, 3p3, 3s3p3d, 3p23d, 3s3d2, 3p3d2, 3s24s, 3s24p, 3s3p4s and 3s24d configurations in Fe XIV. The lifetimes of excited levels belonging to these configurations of Fe XII and Fe XIV are also presented. An accurate representation of the levels has been obtained using spectroscopic and correlation radial functions. The wavefunctions exhibit large correlations and significant dependence of one-electron valence orbitals due to both the total and intermediate terms. The relativistic corrections are included through the one-body and two-body operators in the Breit-Pauli Hamiltonian. Progressively larger calculations are performed to check for important electron correlation contributions and for convergence of results. The atomic wavefunctions give excitation energies which are in close agreement with experiment. The present oscillator strengths and transition probabilities compare very well with previous large scale calculations.  相似文献   

6.
Energy levels, line strengths, oscillator strengths, radiative decay rates, and fine-structure collision strengths are presented for the Zn-like ions Nb XII and Mo XIII. The atomic data are calculated with the AUTOSTRUCTURE code, where relativistic corrections are introduced according to the Breit–Pauli distorted wave approach. We present the calculations of atomic data for 110 fine-structure levels generated from fifteen configurations (1s22s22p63s23p63d10)4s2, 4s4p, 4p2, 4s4d, 4s4f, 4s5s, 4p4d, 4s5p, 4s5d, 4p4f, 4p5s, 4d2, 4d4f, 4f2, and 3d94s24p. Fine-structure collision strengths for transitions from the ground and the first four excited levels are presented at six electron energies (20, 50, 80, 110, 150, and 180 Ryd). Our atomic structure data are compared with the available experimental and theoretical results.  相似文献   

7.
Effective collision strengths are presented for the Fe-peak element Fe III at electron temperatures (Te in degrees Kelvin) in the range 2 × 103 to 1 × 106. Forbidden transitions results are given between the 3d6, 3d54s, and the 3d54p manifolds applicable to the modeling of laboratory and astrophysical plasmas.  相似文献   

8.
Wavelengths, transition rates, and line strengths are calculated for the 76 possible multipole (E1, M1, E2, M2, E3, and M3) transitions between the excited 3s23p63d94l, 3s23p53d104l, and 3s3p63d104l and the ground 3s23p63d10 states in Ni-like ions with the nuclear charges ranging from Z = 30 to 100. The relativistic many-body perturbation theory (RMBPT), including the Breit interaction, is used to evaluate energies and transition rates for multipole transitions in hole-particle systems. This method is based on relativistic many-body perturbation theory, agrees with MCDF calculations in lowest-order, includes all second-order correlation corrections, and includes corrections from negative energy states. The calculations start from a 1s22s22p63s23p63d10 Dirac-Fock potential. First-order perturbation theory is used to obtain intermediate-coupling coefficients, and the second-order RMBPT is used to determine the matrix elements. The contributions from negative-energy states are included in the second-order E1, M1, E2, M2, E3, and M3 matrix elements. The resulting transition energies and transition rates are compared with experimental values and with results from other recent calculations. As a result, we present wavelengths and transition rates data for the selected transitions that include the 76 possible multipole (E1, M1, E2, M2, E3, and M3) transitions between the excited 3s23p63d94l, 3s23p53d104l, and 3s3p63d104l states and the ground 3s23p63d10 state in Ni-like ions. Trends of the line strengths for the 76 multipole transitions and oscillator strengths for the 13 E1 transitions as function of Z are illustrated graphically. The Z-dependence of the energy splitting for all triplet terms of the 3s23p63d94l, 3s23p53d104l, and 3s3p63d104l configurations are shown in the range of Z = 30-100.  相似文献   

9.
A large-scale configuration interaction (CI) calculation using CIV3 is performed for the 303 fine-structure levels of the aluminum-like titanium ion. We have calculated the energy levels, oscillator strengths, and transition probabilities for the electric dipole allowed and intercombination transitions among the levels of ground state 3s23p (2po) and higher energy levels of states 3s3p2, 3p3, 3s3p3d, 3p23d, 3s24s, 3s3d2, 3s24p, 3s3p4s, 3s3p4p, 3p3d2, 3s3p4d, 3s3p4f, 3s25p, 3p24p, 3s3d4s, 3s3p5s, 3s3d4p, 3s3p5p, 3s2(4d, 4f, 5s, 5d, 5f, 6s, 6p, 6d, 6f) of Ti X in the LSJ coupling scheme. The calculations include all the major correlation effects. We attempt to correct the inaccuracies in the CI coefficients in the wavefunctions, which would lead to inaccuracies in transition probabilities by applying a “fine-tuning” technique. The relativistic effects are incorporated by adding the mass correction, Darwin, and spin-orbit interaction terms into the non-relativistic Hamiltonian in the Breit-Pauli approximation. The present results are in good agreement with other available calculations and experiments. Several new lines corresponding to 3s3pnl (n = 4, 5 and l = 0, 1), 3s25p, 3s2(6s, 6p) and other configurations are predicted where no other theoretical or experimental results are available. We expect that our extensive calculations will be useful to experimentalists in identifying the fine-structure levels in their future work.  相似文献   

10.
We have calculated fine-structure energy levels, oscillator strengths and transition probabilities for transitions among the terms belonging to the 1s22s22p6ns (2S), 1s22s22p6np (2P), 1s22s22p6nd (2D) (n = 3, 4, 5), and 1s22s22p6nf (2F) (n = 4, 5) configurations. The calculations are based upon the general configuration-interaction code CIV3 of Hibbert which uses orthonormal orbitals of radial functions expressed as superpositions of normalized Slater-type orbitals. Our calculated values are compared with experimental and other theoretical results where a satisfactory agreement is found. We also report on some unpublished energy values and oscillator strengths.  相似文献   

11.
Fine-structure calculations of energy levels, oscillator strengths, and transition probabilities for transitions among the terms belonging to 3s23p2, 3s3p3, 3s23p3d, 3s23p4s, 3s23p4p, 3s23p4d, 3s23p5s and 3s23p5p configurations of silicon-like ions P II, S III, Cl IV, Ar V and K VI have been calculated using configuration-interaction version 3 (CIV3). We compared our data with the available experimental data and other theoretical calculations. Most of our calculations of energy levels and oscillator strengths (in length form) show good agreement with both experimental and theoretical data. Lifetimes of the excited levels are also given.  相似文献   

12.
Electron impact collision strengths, energy levels, oscillator strengths, and spontaneous radiative decay rates are calculated for Ni XIV. We include in the calculations all the configurations belonging to the n=3 complex, and provide data for the lowest 143 fine-structure levels, belonging to the configurations 3s23p3, 3s3p4, 3s23p23d, 3p5, 3s3p33d, and 3s23p3d2. Collision strengths are calculated at six incident energies for all transitions: 0.112, 8.07, 21.3, 43.4, 80.3, and 141.8 Ry above the threshold of each transition. Calculations have been carried out using the Flexible Atomic Code. Excitation rate coefficients are calculated as a function of electron temperature by assuming a Maxwellian electron velocity distribution. Using the excitation rate coefficients and the radiative transition rates of the present work, statistical equilibrium equations for level populations are solved at electron densities covering the range of 108-1014 cm−3 and at an electron temperature of , corresponding to the maximum abundance of Ni XIV. Spectral line intensities are calculated, and their diagnostic relevance is discussed. This data set is available in version 6.0 of the CHIANTI database.  相似文献   

13.
The energy levels, oscillator strengths, line strengths, and transition probabilities for transitions among the terms belonging to the 3s23p2, 3s3p3, 3s23p3d, 3s23p4s, 3s23p4p and 3s23p4d configurations of silicon-like ions (Zn XVII, Ga XVIII, Ge XIX, and As XX) have been calculated using the configuration-interaction code CIV3. The calculations have been carried out in the intermediate coupling scheme using the Breit–Pauli Hamiltonian. The present calculations have been compared with the available experimental data and other theoretical calculations. Most of our calculations of energy levels and oscillator strengths (in length form) show good agreement with both experimental and theoretical data. Lifetimes of the excited levels have also been calculated.  相似文献   

14.
Large-scale multiconfiguration Hartree-Fock and Dirac-Fock calculations have been performed for the ground configuration, [Kr]4d104f4, energy levels of the W24+ ion. The relativistic corrections were taken into account in the quasirelativistic Breit-Pauli and fully relativistic Breit (taking into account QED effects) approximations. The role of correlation, relativistic, and QED corrections is discussed. Line strengths, oscillator strengths, and transition probabilities in the Coulomb and Babushkin gauges are presented for the electric quadrupole (E2) transitions among these levels. The magnetic dipole transitions are also investigated. Dependence of the E2 transition probabilities on the gauge condition of the electromagnetic field potential is studied as well.  相似文献   

15.
Energy levels, oscillator strengths, and electron impact collision strengths have been calculated for Ge-, Ga-, Zn-, Cu-, Ni-, and Co-like Au ions. For Ni-like Au, these atomic data are obtained among the levels belonging to the configurations of ([Ne])3s23p63d10, 3s23p63d9nl, 3s23p53d10nl, and 3s 3p63d10nl (n = 4, 5; l = 0, 1, … , n − 1). For other Au ions, more levels have been obtained with special attention to atomic data up to transitions of 5f → 3d for emission or 3d → 5f for absorption. Configuration interactions are taken into account for all levels included. Collision strengths have been obtained at 20 scattered electron energies (5-40,000 eV) and they are listed at six representative energies of 100, 500, 1000, 5000, 10,000, and 20,000 eV in this work. Effective collision strengths have been obtained by assuming a Maxwellian electron velocity distribution at 10 representative temperatures ranging from 500 to 5000 eV. The present dataset should be adequate for most applications. The energy levels are expected to be accurate to within 0.5%, while oscillator strengths and collision strengths for strong transitions are probably accurate to better than 20%. The complete dataset is available electronically from http://www.astronomy.csdb.cn/EIE/.  相似文献   

16.
An extensive set of oscillator strengths, line strengths, and radiative decay rates for the allowed and forbidden transitions in Fe XIX is presented. They correspond to 1626 fine structure levels of total angular momenta 0≤J≤8 of even and odd parities with 2≤n≤10, 0≤l≤9, 0≤L≤10, and (2S+1)=1, 3, 5. In contrast, the compiled table of the National Institute for Standards and Technology (NIST) lists only 63 observed levels. A total of 289,291 electric dipole allowed transitions are presented. They were obtained in the close coupling approximation using the relativistic Breit-Pauli R-matrix method. The wavefunction expansion included 15 levels of the configurations 2s22p3, 2s2p4, and 2p5 of the Fe XX core. The calculated fine structure levels are assigned with spectroscopic identifications using quantum defect analysis. Comparison with the observed energies shows very good agreement, the largest difference being less than 4%. The transitions also compare well with the compiled data by NIST and recent calculations. The forbidden transitions of the electric quadrupole and octupole, and magnetic dipole and quadrupole, type are presented for the 379 levels of the configurations 2s22p4, 2s2p5, 2p6, 2s22p33s, 2s22p33p, 2s22p33d, 2s22p34s, 2s22p34p, 2s22p34d, 2s22p34f, 2s2p43s, 2s2p43p, 2s2p43d, 2s2p44s, 2s2p44p, and 2s22p23s2 of Fe XIX. They correspond to a total of 66,619 transitions. These results have been obtained from relativistic Breit-Pauli atomic structure calculations using the program SUPERSTRUCTURE. The forbidden transition probabilities show very good agreement with those compiled by NIST.  相似文献   

17.
Energy levels, transition probabilities, oscillator strengths, line strengths, and lifetimes have been calculated for silicon-like manganese and germanium, Mn XII and Ge XIX. The configurations 3s23p2, 3s3p3, 3s23p3d, 3s3p23d, and 3p4 were used in the calculations and 88 fine-structure levels were obtained. The fully relativistic GRASP code has been adopted, and results are reported for all electric dipole, electric quadrupole, magnetic dipole, and magnetic quadrupole transitions among levels of Mn XII and Ge XIX. Comparisons have been made with available theoretical and experimental results.  相似文献   

18.
We present accurate oscillator strengths and radiative rates for 2173 E1 transitions among the 120 levels belonging to 3s23p4, 3s3p5, and 3s23p3(4So,2Do,2Po)n? configurations where . A configuration interaction approach is employed through the standard CIV3 program. The 114 LS states included in the present calculation generate 250 fine-structure levels belonging to the above configurations below 100,000 cm−1. However, results of only 120 fine-structure levels are presented due to the absence of experimental energy values for the remaining levels. Tabulations of oscillator strengths and radiative rates, and their comparison with other calculations, are presented in the first two tables. In a separate table the oscillator strengths and transition probabilities, in length and velocity gauges, are presented for 2173 E1 transitions, and are arranged in ascending order of wavelength.  相似文献   

19.
We present an extensive, ab initio configuration interaction calculation of oscillator strengths, transition probabilities, and lifetimes of the upper levels of all transitions in Ti VI between the levels of 3s23p5, 3s3p6, 3p43d, 3p44s, 3p44p and 3p44d states in the LSJ coupling scheme. Relativistic effects are incorporated by adding the mass correction, Darwin, and spin-orbit interaction terms to the non-relativistic Hamiltonian in the Breit-Pauli approximation. The calculations incorporate the major correlation effects. The calculated energy levels are in close agreement with most of the NIST tabulation. However, some discrepancies in the energy positions with experimental energies occur in levels with 3p43d 1D and 3P cores, particularly belonging to 2P and 2D symmetries. We predict new data for several levels where no other theoretical and/or experimental results are available. Our extensive calculations will be useful to experimentalists in identifying the fine-structure levels in their future work.  相似文献   

20.
Energy levels, oscillator strengths, and transition probabilities for transitions among the 14 LS states belonging to configurations of sulfur-like iron, Fe XI, have been calculated. These states are represented by configuration interaction wavefunctions and have configurations 3s23p4, 3s3p5, 3s23p33d, 3s23p34s, 3s23p34p, and 3s23p34d, which give rise to 123 fine-structure energy levels. Extensive configuration interaction calculations using the CIV3 code have been performed. To assess the importance of relativistic effects, the intermediate coupling scheme by means of the Breit–Pauli Hamiltonian terms, such as the one-body mass correction and Darwin term, and spin–orbit, spin–other-orbit, and spin–spin corrections, are incorporated within the code. These incorporations adjusted the energy levels, therefore the calculated values are close to the available experimental data. Comparisons between the present calculated energy levels as well as oscillator strengths and both experimental and theoretical data have been performed. Our results show good agreement with earlier works, and they might be useful in thermonuclear fusion research and astrophysical applications.  相似文献   

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