Cluster emissions from neutron-rich 146 Ba, 152 Ce, 156 Nd, 160 Sm, and 164 Gd nuclei are studied within the preformed cluster model of Malik and Gupta. Q-value estimates of the decays selected on the basis of shell effects in binding energies and their relative preformation probabilities show that these nuclei are stable (Q < 0) against 4 He and 10 Be decays and all the metastable (Q > 0) decays are of non-alpha-like heavy clusters. The most probable decays (minimum half-life times) are the ones with a doubly magic 132 Sn nucleus as the daughter nucleus, arising due to the WKB penetrability. Compared to the presently measurable alpha-like cluster decays of the corresponding neutron-deficient parents into a 100 Sn daughter nucleus, these decays are suppressed by many orders of magnitude.

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The nuclear shapes and variation of moment of inertia with angular momentum, as well as the limiting angular momentum carried by a nucleus at its fissioning stage, are derived from the observed data of the ground-state yrast band and quadrupole deformations of these states. The necking-in of the nuclear shapes are shown to start already at J*~14+−18+. The empirical variation of moment of inertia with angular momentum is found to include the back-bending and forward-bending effects and supports the nuclear softness model of the nucleus. The fission of nuclei is shown to occur at very high angular momenta, which is different for different nuclei. The role of deformation energy is analyzed and the possibility of predicting the quadrupole deformations, or B(E2) transitions, for very high spin states is discussed. The calculations are presented for 156Dy, 158Er, and 164Hf.

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