Binding Affinities and Spectroscopy of Complexes Formed by Polysiloxanes with Aniline and Chlorophenol Acetates

Resumo

The theoretical binding energies of the complexes formed by polysiloxanes with aniline and chlorophenol acetates were calculated at B3LYP/6-31G(d, p) level after the basis set superposition error (BSSE) based on B3LYP/6-31G(d) optimized geometries. The high binding energies of the complexes lead to the long experimental retention times in gas chromatography (GC). The energy gaps of the complexes are reduced owing to the formation of the hydrogen bonds. The chemical shifts of the α-C atoms connected to the amino groups in the NMR spectra of the complexes computed with B3LYP/6-31G(d) method are gradually changed downfield as the Si–O chain increases. The aromaticities of the benzene rings in the complexes are decreased due to the transfer of electron clouds from the benzene rings to the Si–O chains based on the nuclear independent chemical shifts (NICS) calculated at B3LYP/6-31G(d) level.