## Tests of microscopic calculations of multiple band structures and large deformations in sup 68 Ge and sup 72 Se

High-spin states in {sup 68}Ge and {sup 72}Se have been studied by in-beam, gamma-ray spectroscopy. In {sup 68}Ge the three known bands beginning at 8{sup +} are found to exhibit crossing transitions and other new positive-parity bands are discovered to feed into them. In {sup 72}Se only a single positive-parity yrast band is seen to high spin. Detailed, more realistic microscopic model calculations have been carried out for {sup 68}Ge and {sup 72}Se. There is striking agreement between the calculations and the new data for {sup 68}Ge, including a predicted new band with superdeformation, {beta}{similar to}0.42. The calculations for {supmore »