Molecular iodine was photoexcited by a strong 800 nm laser, driving several channels of multiphoton excitation. The motion following photoexcitation was probed using time-resolved X-ray scattering, which produces a scattering map $S(Q,tau)$. Temporal Fourier transform methods were employed to obtain a frequency-resolved X-ray scattering signal $tilde{S}(Q,omega)$. Taken together, $S(Q,tau)$ and $tilde{S}(Q,omega)$ separate different modes of motion, so that mode-specific nuclear oscillatory positions, oscillation amplitudes, directions of motions, and times may be measured accurately. Molecular dissociations likewise have a distinct signature, which may be used to identify both velocities and dissociation time shifts, and also can reveal laser-induced couplings among the molecular potentials.
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