[en] The yrast bands of neutron-deficient ^126-130Ce nuclei are studied by using the projected shell model approach. Energy levels, moments of inertia and B(E2) transition probabilities are calculated and compared with the available experimental data. The first and second backbending in ^128,130Ce are investigated. The question as to why the backbending becomes sharp as the neutron number increases in cerium isotopes is addressed. It turns out that the first backbending is caused by a proton pair and the second backbending in ^128,130Ce is due to a simultaneous proton and neutron pair breaking

[en] The projected shell model calculational framework is employed here for studying the nuclear structure determining properties such as high-spin yrast spectra, B(E2) transition probabilities and g-factors for neutron-deficient ^122-128Ba isotopes. It turns out that a dip in B(E2) values and a peak in g-factors are correlated with crossing of the ground state band by multi-quasiparticle bands and alignment of a pair of protons in 1h_11/2 subshell.

[en] Variation after projection (VAP) calculations in conjunction with Hartree-Bogoliubov (HB) ansatz have been carried out for N=60, 62 isotones in the mass region A=100. In this framework, the yrast spectra with J^Π ≥ 10⁺ B(E2) transition probabilities, quadrupole deformation parameter and occupation numbers for various shell model orbits have been obtained. The results of calculations indicate that the simultaneous increase in polarization of p_1/2, p_3/2 and f_5/2 proton sub-shells is a significant factor into the development of the deformation in neutron rich isotones in the mass region A=100.

[en] A systematic study of band structures of some odd mass Samarium isotopes with neutron numbers 91 ≤ N ≤ 95 is carried out by employing projected shell model. The theoretical results have been obtained for band head energies, energy spectra, transition energies and moment of inertia. The calculations on comparison with the experimental data show a reasonably good agreement. The band spectra and transition energies for higher spin states are also predicted in these isotopes. The calculations successfully provide good understanding of the change in structure of the yrast bands and excited bands in terms of single and multi-quasiparticle configurations. The future experimental work will test the predictions made in this paper.

[en] The yrast states and quasiparticle alignments in even–even neutron-deficient xenon isotopes are studied in the projected shell model (PSM) framework. A new set of Nilsson parameters are proposed to reproduce the proton alignments in these isotopes. The B(E2) transition probabilities along the yrast line are obtained from the PSM wave functions and compared with the available experimental data. By using the same wave functions, g-factors are also predicted.

[en] The projected shell model calculations have been carried out in the neutron-rich ^114-124Pd isotopic mass chain. The results have been obtained for the deformation systematics of $E(2_1^{+})$ and $E(4_1^{+})/E(2_1^{+})$ values, BCS subshell occupation numbers, yrast spectra, backbending phenomena, B(E2) transition probabilities and g-factors in these nuclei. The observed systematics of $E(2_1^{+})$ values and $R_{42}$ ratios in the ^114-124Pd isotopic mass chain indicate that there is a decrease of collectivity as the neutron number increases from 68 to 78. The occurrence of backbending in these nuclei as well as the changes in the calculated B(E2) transition probabilities and g -factors predict that there are changes in the structure of yrast bands in these nuclei. These changes occur at the spin where there is crossing of g-band by 2-qp bands. The predicted backbendings and predicted values of B(E2)s and g-factors in some of the isotopes need to be confirmed experimentally.

[en] High spin properties of the neutron-deficient ^66-72Ge isotopes have been studied using the projected shell model approach. In particular, backbending phenomena, B(E2) transition probabilities, and g factors are investigated for these isotopes along the yrast line

[en] Using the angular-momentum projected quasiparticle states and a simple quadrupole–quadrupole + monopole–pairing + quadrupole-pairing type Hamiltonian, Projected Shell Model calculations have been performed to study the nuclear structure properties of some N = 45, 46 isotones in the mass region A = 70–80. The results are obtained for the yrast energy spectrum, rotational alignments, back-bending and reduced transition probabilities [B(M1) and B(E2)]. Results of our calculations exhibit satisfactory agreement with experimental data. Signature splitting and signature inversion which are the characteristics of this mass region have also been reproduced and discussed for these nuclei. (paper)

[en] Aiming at investigating the nuclear structure and the evolution of the deformation in Z = 48 Cd nuclei, which have only two protons less than the Z = 50 magic Sn, we have carried out a microscopic study of negative-parity high-spin states of odd-mass ^111-127 Cd nuclei using the theoretical framework of projected shell model (PSM). The results have been obtained for the deformation systematics of the first excited state $E(15/2^{-<!--\; ???\; -->})$ , yrast energy ratios ( $R_{2/1}$ , yrast spectra, band crossings, backbending phenomena and B(E2) transition probabilities. The present calculations have reproduced the observed nuclear-structure properties quite successfully. It turns out from the results that the gradual and weak deformation in the entire mass chain of the cadmium isotopes under study is intricately linked to the non-degenerate nature of the quasi-particle valence orbits near the Fermi level for neutrons, which hinders the onset of deformations in these isotopes at $N\ge <!--\; ???\; -->60$ . These isotopes are found to have weak prolate deformation in their ground states, ¹¹⁷Cd being the most deformed. Some higher-spin states have also been predicted in this work for which experimental data is not available yet. B(E2) values have also been reported, for the first time, in this work and are open for their experimental verification.

[en] The optical and electrical characteristics of pure, sodium- and lithium-doped potassium hydrogen tartrate crystals grown by the gel technique are reported. An optical absorption study conducted in the UV-Vis range of 200-800 nm reveals the transparency of these crystals in the entire visible range but not in the ultraviolet range. The optical band gap of pure potassium hydrogen tartrate crystals is found to be dependent on doping by Na or Li ions. The non-linear optical behaviour of these crystals is reported and explained. The electrical properties of pure and doped potassium hydrogen tartrate crystals are studied by measuring electrical resistivity from 80 to 300 K. It is shown that while pure potassium hydrogen tartrate crystal is an insulator at room temperature (300 K), doping by Na or Li ions makes it a semiconductor. The results have been explained in terms of the variable range hopping model.