We experimentally demonstrate a coherent-control scheme for precompensation of centrifugal distortion using shaped femtosecond laser pulses. By imposing a cubic spectral phase on the excitation pulse [Y. Huang et al., Phys. Rev. A 107, 053108 (2023)], rotational revivals that would otherwise become temporally broadened, multicycle, and overlap with neighboring rotational contributions are compressed into near single-cycle structures. An analytic expression derived from molecular rotational constants enables predictive pulse design and is validated experimentally. As a stringent demonstration of this control scheme, we achieve transient alignment of distinct $l$-doubling populations in ${\mathrm{CO}}_2$. More broadly, the demonstrated control scheme enables the selective preparation of closely spaced molecular components in controlled anisotropic angular distributions, with direct relevance to molecular-frame spectroscopies and advanced coherent control.

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• Atomic & molecular processes in external fields
• Coherent control
• Light-matter interaction
• Molecular spectra
• Optical transient phenomena
• Rotational states
• Vibrational states