| Abstract
| - To construct two-dimensional infrared (2D IR) spectra having all vibrational modes of a molecule includedis still quite challenging, both experimentally and theoretically. Here we report an ab initio-based all-mode2D IR spectra simulation approach. Using deuterated glycolaldehyde (CH2OHCDO), the smallest sugar as amodel molecule, we have calculated correlation 2D IR spectrum of its entire 3N − 6 (N = 8) normal modesin the mid-to-far-IR region (4000−0 cm-1), using quantum chemical anharmonic frequency and anharmonicitycomputations in conjunction with time-domain third-order nonlinear response functions. The calculated 2DIR spectra were found to contain a network of structural and dynamical parameters of the molecule. It isfound that certain spectral regions, once enlarged, show features that are in reasonable agreement with limitedbut already available single- and dual-frequency 2D IR experimental results. The extension of narrow-band2D IR spectroscopy into the full mid-to-far-IR regime would allow us to characterize the structural distributionsand dynamics of molecular complexes in condensed phases with sufficient number of parameters.
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