G. P. Anisimova

Probabilities of electric dipole transitions in the spectra of ions of the erbium isoelectronic sequence

The probabilities of the 4f136p→4f13ns (n=6 and 7) electric dipole transitions are calculated for the spectra of YbIII, LuIV, and HfV ions of the erbium isoelectronic sequence. The wave functions of the intermediate coupling scheme, which are necessary for calculating the relative line strengths, are semiempirically obtained from experimentally measured energy intervals between the fine-structure levels. To pass to the absolute values, radial integrals of transitions are used, which are evaluated with the Hartree-Fock functions.

Determination of gyromagnetic ratios from the Zeeman splitting of levels of the 3p5f configuration of the silicon atom

We have studied the Zeeman structure of the 3p5f configuration of SiI and revealed its particular features in the range of variation of the magnetic field from 0 to 60 kOe. In this range, we have found 71 crossings of Zeeman sublevels with ΔM = ±1 and ±2 (M is the magnetic quantum number) and 4 anticrossings of lower F levels with j1 = 1/2 (j1 is the total angular momentum of the p electron). From splittings of levels in the assured linear range up to 40 Oe, we have calculated gyromagnetic ratios and compared them with their counterparts in the absence of the field.

Zeeman structure of the 1s5g and 1s6g configurations of helium

The splitting of levels of the 1s5g and 1s6g configurations of the helium atom in an external magnetic field (0–160 Oe) is obtained by using the fine-structure parameters calculated semiempirically. For each configuration, more than 50 crossings and three anticrossings of Zeeman sublevels are determined. The calculated splittings are compared with those obtained earlier for the 1snp and 1snd configurations of a neutral helium atom.

Semiempirical calculation of the fine-structure parameters for np 5 n′p configurations

The fine-structure parameters are calculated semiempirically in the intermediate coupling scheme for the np5n′p configurations of rare gas atoms and a number of ions. The calculation is based on the two-electron matrix of the energy operator, which takes into account, along with the electrostatic interaction, all magnetic interactions. Diagonalizing the energy matrix with the calculated values of the fine-structure parameters yields energy values exactly coinciding with the experimental data, as well as the coupling coefficients and the gyromagnetic ratios. The results obtained are compared with the available literature data.

A semiempirical calculation of the fine and Zeeman structure of 4p4f and 4p5f configurations of Ge I. Gyromagnetic ratios

The gyromagnetic ratios (g-factors) belong to the most important characteristics of atoms. For the 4p4f configuration of a germanium atom experimental values of g-factors are available only for four levels, while similar experimental data on the 4p5f configuration of Ge I are absent. Therefore, a theoretical study of the fine and Zeeman structures is topical for determining the gyromagnetic ratios. All the calculations are performed in the one-configuration approximation with the energy-operator matrix containing a maximum possible number of interactions, including magnetic: spin-orbit (own and other), spin-spin, and also orbitorbit interaction. The fine structure has been examined in three (LS, LK, and jK) approximations in order to establish the nature of coupling in the systems studied and the reliability of g-factors. Apart from the g-factors, in studying the Zeeman splitting, its specific features—the crossing and anticrossing fields of magnetic components— have been determined. A comparative analysis of g-factors was performed that showed that our results are in agreement with the available, albeit few in number, experimental data. At all stages, the corresponding energy-operator matrices were numerically diagonalized, i.e., all the results presented in the paper were obtained in the intermediate coupling scheme.

Zeeman splitting, its specific features, and gyromagnetic ratios for configurations 1snf (n = 4–10) of the helium atom

The fine structure parameters of configurations 1snf (n = 4–10) with new refined energy values are calculated by the semiempirical method. The emphasis is on the study of the Zeeman structure in order to determine the gyromagnetic ratios of all four the levels of the configuration from the splitting. For this purpose, the matrices of an energy operator with allowance for the interaction between the atom and a magnetic field were diagonalized for all possible values of quantum number M. For each configuration, 17 values of crossing fields of the Zeeman sublevels with ΔМ = ±1, ±2 and the regions of anticrossings with ΔМ = 0 were determined. It is remarkable that, because the levels are closely spaced, anticrossings are observed for each pair of levels in these systems. The regions of linearity of a magnetic field, which are different for different configurations, and the levels in them are established. The g-factors are calculated from the coefficients of an intermediate coupling scheme in a magnetic field that is guaranteed to be linear. They are compared with the analogous values in the absence of a field.

Spin-other-orbit interaction in highly excited configurations with p and g electrons in outer shells

The matrix of the operator of the spin-other-orbit interaction energy is constructed for npn’g and np5n’g configurations. The matrix elements of this operator are calculated in the single-configuration approximation with wave functions in the LSJM representation and in the representation of uncoupled angular momenta using the known general formulas. The spin-other-orbit interaction is represented by three direct and three exchange radial Marvin spin interaction integrals.

Calculation of the fields of crossing for the 1s7h configuration of helium

The picture of magnetic level splitting for the 1s7h configuration of helium is calculated with the fine-structure parameters obtained by the semiempirical method. Only the terms linear in the magnetic field strength are taken into account in the matrix elements of the energy operator of interaction of the atom with the magnetic field. In the region of magnetic field strength up to 30 Oe, 4 anticrossings and 73 crossings of the magnetic sublevels were found. Based on the pure

Specific features of Zeeman structure of configurations 2p55g of Ne I and 3p55g of Ar I

j_1 j_2 m_{j_1 } m_{j_2 }