Density Functional Theory Study of the Interaction between Thymine and Luteolin

The density function B3LYP method has been used to optimize the geometries of the luteolin, thymine and luteolin-thymine complexes at 6-31+G*? basis. The vibrational frequencies have been studied at the same level to analyze these seventeen complexes, respectively. Theories of atoms in molecules (AIM) and natural bond orbital (NBO) have been utilized to investigate the hydrogen bonds involved in all the systems. The interaction energies of the complexes corrected by basis set superposition error are between -93.00-76.69 kJ/mol. The calculating results indicate that strong hydrogen bonding interactions have been found in the luteolin-thymine complexes.