The high-spin structure of 100Rh

High-spin states of ¹⁰⁰Rh have been populated with the reactions ⁹⁹Ru(α, 2np) and ⁹⁸Mo(⁶Li, 4n) and their γ-decay has been studied with Ge(Li) detectors in singles and coincidence. Angular and time distributions of the γ-rays were also measured. As a result 14 new levels spanning spins up to I = 16 built on the 5⁺, 4.5 min isomer at 107 keV have been established, and a half-life of $\text{T}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{= 120 ± 5}$ nsec has been determined for the 7⁺ state at 111.9 keV. The rotor-plus-two-quasiparticle model has been used to describe the observed level structure. The pn interaction is shown to be of negligible effect. On the other hand, the introduction of a soft core is essential. The application of the VMI model with the parameters extracted from the ⁹⁸Ru core yields a remarkably good agreement. This is the first time that the anomalous VMI root $\text{(}\text{I}{}_0\text{< 0)}$ has been applied to a doubly odd nucleus.