TESTS OF MICROSCOPIC CALCULATIONS OF MULTIPLE BAND STRUCTURES AND LARGE DEFORMATIONS IN GE-68 AND SE-72

High-spin states in Ge-68 and Se-72 have been studied by in-beam, gamma-ray spectroscopy. In Ge-68 the three known bands beginning at 8+ are found to exhibit crossing transitions and other new positive-parity bands are discovered to feed into them. In Se-72 only a single positive-parity yrast band is seen to high spin. Detailed, more realistic microscopic model calculations have been carried out for Ge-68 and Se-72. There is striking agreement between the calculations and the new data for Ge-68, including a predicted new band with superdeformation, beta approximately 0.42. The calculations for Se-72 predict similar multiple band structures that are not seen experimentally.