NUCLEAR-STRUCTURE IN ODD-ODD NUCLEI, -LESS-THAN-OR-EQUAL-TO-A-LESS-THAN-OR-EQUAL-TO-194

A comprehensive review of the present understanding, bath theoretical and experimental, of intrinsic and rotational level structures in medi um-heavy deformed odd-odd nuclei is presented. A discussion of the var ious experimental methods is presented, emphasizing the need for a var iety of experimental approaches. The odd-odd nuclei that are immediate ly amenable to fruitful additional study are pointed out. A discussion of the intrinsic level structures, Gallagher-Moszkowski (GM) splittin gs, Newby (N) shifts, and role of the residual p-n interaction is pres ented. Currently available data in the rare-earth region allow the emp irical determination of 137 GM splittings and 36 N shifts for 25 odd-o dd nuclei in the mass region 152 less than or equal to A less than or equal to 188. A new parametrization of the residual p-n interaction is presented which also takes into account the 27 GM splittings and 12 N shifts from the actinide region. Newly discovered features of rotatio nal bands, such as odd-even staggering, and other high-spin phenomena, such as signature inversion and delay in bandcrossing frequency, are discussed. The role of higher-order Coriolis coupling is pointed out. Systematics of the two-quasiparticle excitations, shape coexistence, i somers, and four-quasiparticle states are presented. Calculated result s of the two-quasiparticle intrinsic excitations using two methods, th e intrinsic level spacings for odd-A neighboring nuclei and the quasip article-plus-phonon coupling model, are compared with experiment. [S00 34-6861(98)00203-7].