Abstract
The splitting and the displacement of low-lying π g ν f and π d ν f multiplets in the odd-odd N = 83 isotones are found to be described by a quadrupole interaction between the odd proton and odd neutron. The quenching and inversion of the π d ν f parabola is found to arise from the quasiparticle blocking effect as the occupancy of the d 5 2 orbital changes. © 1983.