Structure of odd ^(79,81,83)Se isotopes with proton and neutron excitations across Z=28 AND N= 40

The recently measured experimental data of $^{79,81,83}$Se isotopes have been interpreted in terms of shell model calculations. The calculations have been performed in ${f_{5/2}pg_{9/2}}$ space with the recently derived interactions, namely with JUN45 and jj44b. To study the importance of the proton excitations across the $Z=28$ shell in this region. We have also performed calculation in ${fpg_{9/2}}$ valence space using an ${fpg}$ effective interaction with $^{48}$Ca core and imposing a truncation. Excitation energies, $B(2)$ values, quadrupole moments and magnetic moments are compared with experimental data when available. Present study reveals the importance of proton excitations across the $Z=28$ shell for predicting quadrupole and magnetic moments.