The interaction of carbohydrates and amino acids with aromatic systems studied by density functional and semi-empirical molecular orbital calculations with dispersion corrections

Raman Sharma, Jonathan P. McNamara, Rajesh K. Raju, Mark A. Vincent, Ian H. Hillier, Claudio A. Morgado

Research output: Contribution to journalArticle

44 Citations (Scopus)

Abstract

Density functional theory (DFT-D) and semi-empirical (PM3-D) methods having an added dispersion correction have been used to study stabilising carbohydrate-aromatic and amino acid-aromatic interactions. The interaction energy for three simple sugars in different conformations with benzene, all give interaction energies close to 5 kcal mol-1. Our original parameterization of PM3 (PM3-D) seriously overestimates this value, and has prompted a reparametrization which includes a modified core-core interaction term. With two additional parameters, the carbohydrate complexes, as well as the S22 data set, are well reproduced. The new PM3 scheme (PM3-D*) is found to describe the peptide bond-aromatic ring interactions accurately and, together with the DFT-D method, it is used to investigate the interaction of six amino acids with pyrene. Whilst the peptide backbone can adopt both stacked and T-shaped structures in the complexes with similar interaction energies, there is a preference for the unsaturated ring to adopt a stacked structure. Thus, peptides in which the latter interactions are maximised are likely to be the most effective for the functionalisation of carbon nanotubes.

Original languageEnglish
Pages (from-to)2767-2774
Number of pages8
JournalPhysical Chemistry Chemical Physics
Volume10
Issue number19
DOIs
Publication statusPublished - 2008
Externally publishedYes

    Fingerprint

ASJC Scopus subject areas

  • Physical and Theoretical Chemistry
  • Atomic and Molecular Physics, and Optics

Cite this