Shell Structures in 91 Nb

High spin states of 91Nb are populated via the fusion-evaporation reaction 76Ge (19F, 4n)91 Nb at the beam energy of 80 MeV. The existing level scheme is modified and extended to higher spins. Its low-lying states are well described by the weakly coupling between a g9/2 proton and the even-even 90Zr core, whereas the higher level structures could be interpreted by the multi-particle excitations in the model space p(1/5/2, 2p1/2,1g9/2) n (1g9/2, 2d5/2, 1g7/2) in the framework of the shell model.