Photofragmentation dynamics of N,N-dimethylformamide following excitation at 193 nm

摘要

N,N-dimethylformamide, HCON(CH3)2, is a useful model compound forinvestigating peptide bond photofragmentation dynamics. We report datafrom a comprehensive experimental and theoretical study into the photofragmentationdynamics of N,N-dimethylformamide in the gas phase at 193 nm.Through a combination of velocity-map imaging and hydrogen atom Rydbergtagging photofragment translational spectroscopy, we have identifiedtwo primary fragmentation channels, namely fission of the NCO `peptide'bond, and NCH3 bond fission leading to loss of CH3. The possible fragmentationchannels leading to the observed products are rationalised withrecourse to CASPT2 calculations of the ground and first few excited-statepotential energy curves along the relevant dissociation coordinates, and theresults are compared with data from previous experimental and theoretical studies on the same system.