Unraveling the Conformational Landscape of Triallyl Phosphate: Matrix Isolation Infrared Spectroscopy and Density Functional Theory Computations

The conformations of triallyl phosphate (TAP) were studied using matrix isolation infrared spectroscopy and density functional theory (DFT) calculations. TAP was trapped in N2, Ar, and Xe matrixes at 12 K using an effusive source and the resultant infrared spectra recorded. The computational analysis on conformers of TAP is a challenging problem due to the presence of the large number of conformations. To simplify this problem, conformational analysis was performed on prototypical molecules such as dimethyl allyl phosphate (DMAP) and diallyl methyl phosphate (DAMP), to systematically arrive at the conformations of TAP. The above methodology discerned 131 conformations for TAP, which were found to contribute to the room temperature population. The computations were performed using B3LYP/6-311++G(d,p) level of theory. Vibrational wavenumber calculations were performed for the various conformers to assign the experimental infrared features of TAP, trapped in solid N2, Ar, and Xe matrixes.