The very neutron deficient Z N 1 1 nuclei 77 39 Y, 79 40 Zr, and 83 42 Mo have been observed for the first time following the fragmentation of a 92 Mo beam. In contrast, no evidence was found for the existence of 81 41 Nb and 85 43 Tc. The observation of 77 39 Y is of particular interest in light of the instability of the oddproton, Z N 1 1 systems, 69 35 Br, 73 37 Rb, 81 41 Nb, and 85 43Tc, and may be explained as a consequence of the shape polarizing effect of the highly deformed, prolate Z N 38 core. The experimental results are discussed within the framework of the shell-correction model, which together with proton-decay calculations allow an estimate of the proton separation energies of these highly exotic systems to be calculated. [S0031-9007(98)

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In this overview, some latest results from gamma-ray spectroscopic studies of high spin states of isobaric multiplets will be presented. An experimental programme is underway to examine exited states of isobaric multiplets of total isospin T --89 and T = 1 and the comparison of energies of excited states can be interpreted in terms of Coulomb effects. Through a systematic study of these Coulomb effects, and through examination of the calculated Coulomb energies from full p f-shell model calculations, it is now becoming clear that measurement of Coulomb energies can yield very detailed information on the evolution of nuclear structure phenomena as a function of energy and angular momentum. In this contribution, latest results of studies of isobaric analogue states at high spin in the A = 50, 51 and 53 systems will be presented.