New level schems of Y and Nb isotopes are proposed based on measurements of prompt gamma rays from 252Cf fission at Gammasphere. Shape trends regarding triaxiality and quadrupole deformations are studied.

The structure of Tc nuclei is extended to the more neutron-rich regions based on measurements of prompt gamma rays from the spontaneous fission of 252Cf at Gammasphere. The level scheme of N=67 neutron-rich (Z=43) 110Tc is established for the first time and that of 111Tc is expanded. The ground-state band of 111Tc reaches the band-crossing region and the new observation of the weakly populated alpha = -1/2 member of the band provides important information of signature splitting. The systematics of band crossings in the isotopic and isotonic chains and a CSM calculation suggest that the band crossing of the gs band of 111Tc is due to alignment of a pair of h11/2 neutrons. The best fit to signature splitting, branching ratios, and excitations of the ground-state band of 111Tc by RTRP model calculations result in a shape of epsilon2 = 0.32 and gamma = -26 deg. for this nucleus. Its triaxiality is larger than that of 107Tc, to indicate increasing triaxiality with increasing neutron number. The identification of the weakly-populated "K+2 satellite" band provides strong evidence for the large triaxiality of 111Tc. In 110Tc the four lowest-lying levels observed are very similar to those in 108Tc. At an excitation of 478.9 keV above the lowest state observed, ten states of a delta I = 1 band are observed. This band is very analogous to the delta I = 1 bands in 106,108Tc, but it has greater signature splitting at higher spins.