Broken Pair Model: A viable Alterative to the Shell Model for Odd-Spherical Nuclei

The broken pair model has been developed earlier as an useful approximation to the nuclear shell model for even-even nuclei. It is extended and developed here to include odd nuclei too. The model is then applied successfully in the Zr region, using two different sets of matrix elements, the empirical and the realistic sussex ones. The broken pair model results show a considerable agreement with the shell model results wherever available and with the experimental data where shell model calculations are not performed yet.