Signatures of different vibrational modes in strong-field fragmentation of diiodomethane

The diiodomethane molecule (CH$_{2}$I$_{2})$ has served as a model system for time-domain studies of large-scale bending vibrations and concerted elimination of I$_{2}^{+}$ [1]. Here we present the results of a time-resolved 3D Coulomb explosion imaging experiment on diiodomethane that maps ultrafast dynamics of both, bound and dissociating nuclear wave packets driven by a strong laser field. Measuring yields, kinetic energies and emission angles of coincident ionic fragments as a function of time delay between two 25 fs, 800 nm pump and probe pulses, we track the propagation of different dissociation pathways and visualize vibrational motion of the molecule. Analyzing channel-selective Fourier spectra, we observe signatures of both, bending and stretching vibrations of diiodomethane, and reveal correlation between bending motion (the I-C-I ``scissors'' mode) and different fragmentation pathways, including I$_{2}^{+}$ elimination. [1] D. Gei{\ss}ler \textit{et al}., J. Chem. Phys. \textbf{127}, 204305 (2007).