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Updated: Mar 1, 2026
Construction and Systematical Symmetric Studies of a Series of Supramolecular Clusters with Binary or Ternary Ammonium Triphenylacetates
Published on: February 15, 2016
Effects of Alkyl Groups on Excess-Electron Binding to Small-Sized Secondary Amide Clusters: A Combined Experimental
Toshihiko Maeyama1, Takuto Shimamori1, Asuka Fujii1
1Department of Chemistry, Graduate School of Science, Tohoku University , Aoba-ku, Sendai 980-8578, Japan.
Abstract:
Excess-electron binding to dimers and trimers of secondary amide molecules was studied by a combination of photoelectron spectroscopy and theoretical calculations. Vertical detachment energies (VDEs) of the cluster anions were measured in the range of a few hundred millielectronvolts. We found a tendency for VDE to decline with extension of alkyl side chains. It was fairly reproduced by results of quantum chemical calculations based on density functional theory. For the optimized structures of the cluster anions, the excess electron is located diffusively around the dangling NH group of the hydrogen-bond acceptor molecule. Dipole moment values calculated for the vertically detached neutrals are consistent with the motif of dipole-bound anions. Alkyl groups are likely to inhibit a close interaction between the excess electron and amide groups. It appears to be incompatible with a previously reported trend that the yield of the trimer anions is enhanced with extension of the side chains.
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