A revised version of Grasp2K [P. Jönsson, X. He, C. Froese Fischer, and I.P. Grant, Comput. Phys. Commun. 177 (2007) 597] is presented. It supports earlier non-block and block versions of codes as well as a new block version in which the njgraf library module [A. Bar-Shalom and M. Klapisch, Comput. Phys. Commun. 50 (1988) 375] has been replaced by the librang angular package developed by G. Gaigalas based on the theory of C. Froese Fischer, J. Phys. B: At. Mol. Phys. 30 (1997) 3747, G. Gaigalas, S. Fritzsche, and I.P. Grant, Comput. Phys. Commun. 139 (2001) 263]. Tests have shown that errors encountered by njgraf do not occur with the new angular package. The three versions are denoted v1, v2, v3, respectively. In addition, in v3, the coefficients of fractional parentage have been extended to j = 9/2, making calculations feasible for the lanthanides and actinides. Changes in v2 include minor improvements. For example, the new version of rci2 may be used to compute QED corrections only from selected orbitals. In v3 a new program, jj2lsj, reports the percentage composition of the wave function in LSJ and the program rlevels has been modified to report the CSF with the largest coefficient of an LSJ expansion. The bioscl2 and bioscl3 application programs have been modified to produce a file of transition data with one record for each transition in the same format as in Nature of problem:Prediction of atomic properties -atomic energy levels, oscillator strengths, radiative decay rates, hyperfine structure parameters, Landé g J -factors, and specific mass shift parameters -using a multiconfiguration Dirac-Hartree-Fock approach. Solution method:The computational method is the same as in the previous Grasp2K [1] version except that for v3 codes the njgraf library module [2] for recoupling has been replaced by librang [3,4]. Restrictions:The packing algorithm restricts the maximum number of orbitals to be ≤ 214. The tables of reduced coefficients of fractional parentage used in this version are limited to subshells with j ≤ 9/2 [5]; occupied subshells with j > 9/2 are, therefore, restricted to a maximum of two electrons. Some other parameters, such as the maximum number of subshells of a configuration state function (CSF) outside a common set of closed shells are determined by a parameter.def file that can be modified prior to compile time. Unusual features:The bioscl3 program reports transition data in the same format as in Atsp2K[6], and the data processing program tables of the latter package can be used.The tables program takes a name.lsj file, usually a concatenated file of all the .lsj transition files for a given atom or ion, and finds the energy structure of the levels and the multiplet transition arrays. The tables posted at the website 3 http://atoms.vuse.vanderbilt.edu are examples of tables produced by the tables program. With the extension of coefficients of fractional parentage to j = 9/2, calculations for the lanthanides and actinides become possible.

The neutron-rich isotopes of cadmium up to the N ¼ 82 shell closure have been investigated by highresolution laser spectroscopy. Deep-uv excitation at 214.5 nm and radioactive-beam bunching provided the required experimental sensitivity. Long-lived isomers are observed in 127 Cd and 129 Cd for the first time. One essential feature of the spherical shell model is unambiguously confirmed by a linear increase of the 11=2 À quadrupole moments. Remarkably, this mechanism is found to act well beyond the h 11=2 shell. DOI: 10.1103/PhysRevLett.110.192501 PACS numbers: 21.10.Ky, 21.60.Cs, 31.15.aj, 32.10.Fn When first proposed, the nuclear shell model was largely justified on the basis of magnetic-dipole properties of nuclei [1]. The electric quadrupole moment could have provided an even more stringent test of the model, as it has a very characteristic linear behavior with respect to the number of valence nucleons [2,3]. However, the scarcity of experimental quadrupole moments at the time did not permit such studies. Nowadays, regardless of experimental challenges, the main difficulty is to predict which nuclei are likely to display this linear signature. The isotopes of cadmium, investigated here, proved to be the most revealing case so far. Furthermore, being in the neighborhood of the ''magic'' tin, cadmium is of general interest for at least two additional reasons. First, theory relies on nuclei near closed shells for predicting other, more complex systems. Second, our understanding of stellar nucleosynthesis strongly depends on the current knowledge of nuclear properties in the vicinity of the doubly magic tin isotopes [4]. Moreover, specific questions concerning the nuclear structure of the cadmium isotopes require critical evaluation, such as shell quenching [5,6], sphericity [7], deformation [8,9], or whether vibrational nuclei exist at all [10]. Some of these points will be addressed here quite transparently, while others require dedicated theoretical work to corroborate our conclusions. In this Letter we report advanced measurements by collinear laser spectroscopy on the very neutron-rich cadmium isotopes. Electromagnetic moments in these complex nuclei are found to behave in an extremely predictable manner. Yet, their description goes beyond conventional interpretation of the nuclear shell model.The measurements were carried out with the collinear laser spectroscopy setup at ISOLDE-CERN. High-energy protons impinging on a tungsten rod produced low-to medium-energy neutrons inducing fission in a uranium carbide target. Proton-rich spallation products, such as cesium, were largely suppressed in this manner. Further reduction of surface-ionized isobaric contamination was achieved by the use of a quartz transfer line [11], which allowed the more volatile cadmium to diffuse out of the target while impurities were retained sufficiently long to decay. Cadmium atoms were laser ionized, accelerated to an energy of 30 keV, and mass separated. The ion beam was injected into a gas-filled radio-frequency Paul trap [12]...

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Tin is the chemical element with the largest number of stable isotopes. Its complete proton shell, comparable with the closed electron shells in the chemically inert noble gases, is not a mere precursor to extended stability; since the protons carry the nuclear charge, their spatial arrangement also drives the nuclear electromagnetism. We report high-precision measurements of the electromagnetic moments and isomeric differences in charge radii between the lowest 1/2+, 3/2+, and 11/2− states in 117–131Sn, obtained by collinear laser spectroscopy. Supported by state-of-the-art atomic-structure calculations, the data accurately show a considerable attenuation of the quadrupole moments in the closed-shell tin isotopes relative to those of cadmium, with two protons less. Linear and quadratic mass-dependent trends are observed. While microscopic density functional theory explains the global behaviour of the measured quantities, interpretation of the local patterns demands higher-fidelity modelling.

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We explore QED and many-body effects in superheavy elements up to Z = 173 using the multiconfiguration Dirac-Fock method. We study the effect of going beyond the average-level approximation on the determination of the ground state of element 140, and compare with the recent work of Pekka Pyykkö on the periodic table for super heavy elements [1]. We confirm that QED corrections are of the order of 1% on ionization energies. We show that the atomic number at which the 1s shell dives into the negative energy continuum is 173, and is not affected by the approximation employed to evaluate the electron-electron interaction.

Multiconfiguration Dirac-Fock models have been employed to compute the electric field gradient in the ground state of the neutral bismuth atom. Combined with the experimental electric quadrupole hyperfine interaction constant, one obtains for (209)Bi the nuclear quadrupole moment Q = -516 (15) mb, which is almost 40% away from the previously accepted standard value [ -370 (26) mb], and narrows by over an order of magnitude the long-standing, extremely broad array of various results ranging from -370 to -710 mb. The recent Q values of (202-208,210(m)-213)Bi by Pearson et al. suffer a consequent change.

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