Normal Mode Analysis Coupled Structural Analysis

As the time resolution improves, experimental observation approaches direct visualization of nuclear motions during the photoexcitation, which provides the basis for structural control of light-matter interactions in solar energy conversion. The excited state to final photochemical product trajectories are often initiated by vibrational motions. When photons add energy to molecules, their energy will be dissipated among different vibrational modes. Therefore, carrying out a normal mode analysis (NMA) of the excited state will provide a guide to how the nuclear motions were launched at the very beginning of the photon-matter interaction. In data fitting with MIA and similar methods, it is important to choose the correct nuclear coordinates that are adjusted to generate theoretically calculated spectra that fit the experimental results. So far the choice of the combined coordinates has been mainly based on chemical intuition. If the NMA can be conducted for the excited states, one can gain a much better initial selection of the structural variation along the normal modes, which may consequently generate the correct answers sooner with better fits to the experimental results.

Updated: August 18, 2015 — 1:27 pm