Migration from the normal to the highly deformed minimum in 131Nd

The deformation driving vi(13/2) [660]1/2 structure has been identified for the first time in Nd-131. It is the lightest Nd (Z=60) isotope in which a band based on this intruder orbital has been reported. A crossing between the [411]1/2 band and the [660]1/2 sequence takes place near (h) over bar h omega approximate to 0.34 MeV with a large interaction strength (\V\(max)=47 keV). Thus, a smooth transition from the normal to the highly deformed minimum is established in Nd-131. [S0556-2813(99)50110-6].