Two new low-lying isomeric states and two new rotational bands have been identified in the odd-odd nucleus ${}^{116}\mathrm{Cs}$ from a high-statistics experiment using the ${}^{58}\mathrm{Ni}({}^{64}\mathrm{Zn},\alpha pn$)${}^{116}\mathrm{Cs}$ fusion-evaporation reaction and the JUROGAM $3+\mathrm{MARA}$ setup. The spin-parity of the known $T_{1/2}=3.85\mathrm{s}$ isomer is firmly fixed as $6^{+}$, and its configuration is established as $\pi g_{9/2}^{-1}\otimes \nu g_{7/2}$ from the properties of the strongly coupled band built on it. The $8^{+}$ and $7^{-}$ bandheads of the two rotational bands to which we assign $\pi h_{11/2}\otimes \nu h_{11/2}$ and $\pi h_{11/2}\otimes \nu d_{5/2}$ configurations, respectively, have lifetimes of the order of a few nanoseconds and can therefore be considered as isomeric states. Several weak transitions depopulate the $8^{+}$ isomer, feeding states that can be based on oblate shapes. The analysis of the alignment properties, combined with the systematics of the doubly-odd cesium nuclei, and the results of extensive particle number conserving cranked shell-model calculations, led to a very good understanding of the bands structures. The spins and parities of two bands of ${}^{118}\mathrm{Cs}$ with properties similar to the bands built on the $6^{+}$ and $7^{-}$ isomers of ${}^{116}\mathrm{Cs}$ have been changed to $7^{+}$ and $7^{-}$ and reassigned to the $\pi g_{9/2}^{-1}\otimes \nu g_{7/2}$ and $\pi h_{11/2}\otimes \nu d_{5/2}$ configurations, respectively. The band of ${}^{118}\mathrm{Cs}$ built on the $\pi h_{11/2}\otimes \nu d_{5/2}$ configuration has been extended to higher spin. The new results enrich the band structure in very light cesium nuclei and unveil the existence of multiple high-$K$ and possible shape isomers built on two-quasiparticle configurations close to the proton drip line.

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• Collective levels
• Collective models
• Electromagnetic transitions
• Energy levels
• High spin states
• Nuclear spin & parity
• 90 ≤ A ≤ 149