A multinucleon transfer reaction with a ${}^{136}\mathrm{Xe}$ beam and a gold-backed ${}^{176}\mathrm{Yb}$ target populated isomers in $N=108{}^{178}\mathrm{Yb}$ and ${}^{179}\mathrm{Lu}$. The single decay from the $t_{1/2}=203$(16) ns isomer in ${}^{178}\mathrm{Yb}$ to the $I^{\pi }=4^{+}$ level in the ground-state band suggests a $I^{\pi }=4^{-}$ assignment, and multiquasiparticle calculations associate this state with the $K^{\pi }=4^{-}, {\nu }^2(1/2\left[510\right],9/2\left[624\right])$ configuration. At least two isomers were observed in ${}^{179}\mathrm{Lu}$. One likely couples the $K^{\pi }=4^{-}$ configuration found in ${}^{178}\mathrm{Yb}$ to the $9/2\left[514\right]$ quasiproton orbital to form a $K^{\pi }=17/2^{+}$ level ($t_{1/2}=1.0\left(4\right)\mu \mathrm{s}$) which primarily decays into the rotational band based on the 9/2[514] state. A second isomer was observed to decay into this same band, but at higher energy and spin. Based on its feeding pattern, its similarity to an isomer found in ${}^{181}\mathrm{Ta}$, and a multiquasiparticle calculation, it is proposed to correspond to a $K^{\pi }=29/2^{-}$ state based on the $\pi 9/2\left[514\right]{\nu }^2(9/2\left[624\right],11/2\left[615\right])$ configuration. An analysis of the reduced hindrance factors for negative-parity, two-quasineutron isomers in the rare-earth region is presented as well.

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• Collective levels
• Energy levels
• Isomer decays
• Nuclear structure & decays
• 150 ≤ A ≤ 189