For the first time, excited states of ${}_{}{}^{175}{}_{}{}^{}\mathrm{Ir}$ have been observed. Remarkably different developments with rotation are found in bands built on the [541]1/$2^{\mathrm{-}}$, [505]11/$2^{\mathrm{-}}$, and [660]1/$2^{+}$ orbitals. The data are analyzed within the deformed shell model. The pattern of the [505]11/$2^{\mathrm{-}}$ band is interpreted as a combined stretching and alignment effect. For the [660]1/$2^{+}$ band, an extremely strong interaction with the S band results in an almost entirely smeared out alignment process not explained by standard calculations. This feature might indicate a strong residual pn interaction.

• Received 15 January 1991

DOI:https://doi.org/10.1103/PhysRevC.43.R2031