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In this work, we calculate dynamic polarizabilities and hyperfine-structure A and B constants of a few low-lying states for Sc2+. The sum-over-states technique is applied to calculate the polarizabilities of the 3d ²D3/2, 3d ²D5/2, and 4s ²S1/2 states. The most important and correlation sensitive part of the sum is calculated using a highly correlated relativistic coupled-cluster theory. The remaining part of the sum is calculated using a lower-order many-body perturbation theory and the Dirac-Fock theory. Present dynamic polarizabilities are important to investigate the Stark shifts in the 4S ²S1/2-3d ²D5/2 and 4s ²S1/2-3d ²D3/2 clock transitions of Sc2+. Magic wavelengths for zero Stark shifts corresponding to these transitions are found in the vacuum-ultraviolet region. The coupled-cluster theory is used to estimate the hyperfine A and B constants with a very high accuracy. [ABSTRACT FROM AUTHOR]

In this paper, we have calculated parity nonconserving electric dipole amplitudes of the hyperfine components for the transitions between the ground and first excited states of 137Ba+ and 87Sr+ using sum-over-states technique. The results are presented to extract the constants associated with the nuclear spin-dependent amplitudes from experimental measurements. The wave functions to calculate the most dominant part of the sums are constructed using highly correlated coupled-cluster theory based on the Dirac-Coulomb-Gaunt Hamiltonian. [ABSTRACT FROM AUTHOR]

Hyperfine constants and anomalies of ground as well as a few low-lying excited states of 113,115,117In III are studied with highly correlated relativistic coupled-cluster theory. The ground-state hyperfine splitting of 115In III is estimated to be 106.8 GHz. A shift of almost 1.9 GHz of the above frequency has been calculated due to the modified nuclear dipole moment. This splitting result shows its applicability as communication band and frequency standards at 10-11 s. A correlation study of hyperfine constants indicates a few distinct features of many-body effects in the wave functions in and near the nuclear region of this ion. Astrophysically important forbidden transition amplitudes are estimated. The calculated oscillator strengths of a few allowed transitions are compared with recent experimental and theoretical results wherever available. [ABSTRACT FROM AUTHOR]

In this paper, we have described electron-correlation trends in the calculations of the hyperfine A and B constants for a few elements belonging to the Na isoelectronic sequence. The hyperfine A and B/Q values of the ground state 3s 2S 1/2 and the excited states 3p 2P 1/2, 3p 2P 1/2, 3d 2D 3/2, and 3d 2D 5/2 of the ions from Si 3+ to V 12+ are presented. The influence of the Breit interaction in the unretarded approximation to these hyperfine values is reported briefly. With increasing atomic number of this sequence, the variations of the different correlation contributing terms such as core correlations, core polarizations, and pair correlations are discussed in the framework of the relativistic coupled-cluster theory. The electron-correlation effect relative to the Dirac-Fock value in the hyperfine A constants of the 3d 2D 3/2,5/2 states follows unusual trends with increasing ionization. The relative pair-correlation effect influences the hyperfine constants of the fine-structure states of a term in an identical way at each species of this sequence. The presented relativistic coupled-cluster results are found to agree excellently with the other available results for a few ions. [ABSTRACT FROM AUTHOR]