Theoretical Modeling - PET 4-mer

    The lowest-energy structures predicted for the PET 4-mer are similar to those predicted for the 2-mer. The oligomer folds so that the phenyl groups in the chain stack on top of each other, forming two stacked pairs, and the Na⁺ ion binds to the terminal OH groups and 2-3 carbonyl oxygens. Similar structures were predicted for the PET 4-mers cationized by Li⁺ and K⁺ as well. One slight difference between the three metal cations is that the Li⁺PET4 oligomers are predicted to be slightly bent in the middle (rather than planar as shown below) leading to a smaller overall cross-section, seen in the table (above right).