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The energy level spectrum of Ni58 has been analyzed on the simple considerations of pure singlet s-state forces. By taking the single-particle energy (p3/2-f5/2 spacing) as a free parameter, the best fit is obtained for Δ≈0.9 MeV which is in fair agreement with the experimentally suspected value of 0.85 MeV for the single particle level of Ni57. Many more, as yet unobserved, levels are predicted in the energy range of 2.5–3.2 MeV and it is pointed out that their exact location would be very helpful in understanding the detailed nature of the two-body forces. Finally the extension of the above analysis of the three particle configuration suggests a 3/2− ground state for Ni59.

Elastic and inelastic scattering of 190 Mev electrons by ground and 2.43 Mev states of Be9 is computed by using an intermediate coupling shell model. The discrepancy between the calculated and the observed inelastic cross sections reported earlier is now removed by taking the correct spin value J=5/2- for the 2.43 Mev state. It is shown that a good fit to the observed data requires that different radial extension parameters be chosen for the s- and p-shell nucleons. The best values obtained are a0=1.23 f for the s-shell and 2.0 f for the p-shell.

Zr90 offers a very good case for the study of T=1 levels in the p1/2-g9/2 subshells and has recently been explored by several authros. Here earlier calculations of Thankappan and Waghmare are extended and analysed in detail. It is found that a simple central two-body interaction can be constructed which will give correctly the energy levels of the (g9/2)2 configuration, and hence also the levels of a (g9/2)n configuration. However, the same interaction fails to give correctly the levels of the other configurations (p1/2)(g9/2) and (p1/2)2. This simple two-body nuclear interaction is thus shown to be configuration dependent. It is pointed out that experimental identification of the as yet unobserved 4- level would be very helpful for further elucidation of this phenomenon. The results are compared with those of the other authors.