Background: The organic molecules represent one of the most active classes of
compounds, and they have been widely used as active materials for important applications. In
this study, the organic molecules and their derivatives with electron withdrawing groups in
different positions were investigated to elucidate the influence of substituted groups on
electronic and optical properties.
Objective: In order to guide the synthesis of novel materials, some new organic compounds are
designed as good candidates for nanoelectronics and solar cell applications.
Methods: All the calculations are based on the density functional theory (DFT) at the
B3LYP/6-31G level through the Gaussian 09W program package.
Results: The optimized structures, total energies, electronic states (HOMO and LUMO),
energy gaps and the absorption thresholds were performed. This study clarified that the
electronic and optical properties are sensitive to the type and position of substituted
subgroups. This leads to significant changes in the charge transport and the absorption
spectra. The results showed a decrease in energy gaps and the presence of the electron
withdrawing groups (such as CClO radical) leads to the absorption threshold in the visible
region of the spectrum.
Conclusion: The study of structural, electronic and optical properties for these molecules
could help to design more efficient functional organic materials, and these properties play a
key role in a variety of nanoelectronics and solar cells applications.