High-spin states have been populated in the neutron-deficient ${}^{135,136}\mathrm{Sm}$ nuclei via the ${}^{105}\mathrm{Pd}{(}^{35}\mathrm{Cl},pxn)$ reaction at a beam energy of 180 MeV. Transitions within the Sm nuclei were enhanced by using the Microball charged particle array and $\gamma$-ray de-excitation was studied using Gammasphere. A new highly deformed band has been observed in the data and assigned to ${}^{136}\mathrm{Sm}.$ Comparison of the properties of the new band with Woods-Saxon cranking calculations suggests that it is built upon a $\nu {(i}_{13/2}{)}^2$ configuration. The band shows evidence for an interaction at $ħ\omega \sim 0.7\hspace{0.5em}\mathrm{MeV}.$ This has tentatively been interpreted as resulting from a crossing between the $\alpha =+1/2\mathrm{}$ signatures of the $\left[532\right]5/2$ and $\left[541\right]1/2$ proton orbitals. The previously known $\nu i_{13/2}$ intruder band in ${}^{135}\mathrm{Sm}$ was also observed and extended to higher rotational frequency. Both structures show good agreement with extended total Routhian surface calculations.

• Received 8 December 1997

DOI:https://doi.org/10.1103/PhysRevC.58.3212