The excited rotational bands based on the $\nu 7/2^{+}\left[624\right]$ and $\nu 5/2^{+}\left[622\right]$ configuration in the odd-$N$ 151 isotones, ${}^{245}\mathrm{Pu}$, ${}^{247}\mathrm{Cm}$, and ${}^{249}\mathrm{Cf}$, are analyzed within the framework of the cranked shell model (CSM) with pairing correlations treated by the particle number conserving method (PNC-CSM), in which blocking effects are precisely accounted for. A systematic analysis of empirical parameters of ground-state bands in even-even nuclei highlights that neutron-rich Pu isotope exhibits stronger pairing correlations, which plays a crucial role in shaping the rotational behavior of the ground and excited bands. Microscopic calculation using PNC-CSM confirmed the relative stronger pairing strengths in neutron-rich ${}^{245}\mathrm{Pu}$. The experimental kinematic and dynamic moments of inertia are reproduced very well by the PNC-CSM calculations. The odd-$N$ excited bands allow for a comparison of the alignment behavior for two different configurations, where the $\nu j_{15/2}$ alignment is either blocked or allowed. This study marks the first instance of $\nu j_{15/2}$ alignment, which is otherwise elusive in nature. The present study demonstrates that the inclusion of higher-order ${\epsilon }_6$ deformation plays a crucial role in accurately reproducing the alignment behavior observed in $N=151$ isotones. In particular, ${\epsilon }_6$ deformation significantly delays proton alignment and enhances neutron alignment contributions. Our PNC-CSM calculations confirm that neutron alignment precedes that of $i_{13/2}$ protons in ${}^{249}\mathrm{Cf}$. These findings underscore the importance of incorporating ${\epsilon }_6$ deformation to correctly describe rotational properties in heavy actinide nuclei.

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• Collective levels
• High spin states
• Nuclear spin & parity
• Nuclear structure & decays
• Shell model
• A ≥ 220