Comparison of valence-correlation schemes in nuclei having valence nucleons in the same shell

The variation of excitation energies of yrast 2+ states and ratios E4+/E2+ with NpNn in the mass range of A = 6-136 having valence nucle-ons in the same shell is studied. The mass range A = 6-136 was considered due to the availability of data when valence protons and neutrons fill in the same major shell. It has been noticed that the depression in E2+ and ascension in R appear in isobars that differ from the predictions of the NpNn scheme in which isotones are expected. A new correlation scheme, the product of valence nucleon NT, and holes over bar over bar to explain the experimental observations. NT, i.e., NT NT is proposed