Calculation of the levels of Ni and Sn isotopes by the quasiparticle method

A modified Tamm-Dancoff approximation, developed in a previous paper, has been applied to even Ni and Sn isotopes. Detailed spectra, E2 transition strengths connecting various levels, and the quadrupole moment of the first excited 2+ level have been calculated and the trends of the results compared with experimental values. The method appears to be fairly satisfactory. It points to the necessity of more reliable information on the effective interaction, active single-particle orbitals, and single-particle radial functions in order that a dependable quantitative fit to the data can be achieved.