Geometries and properties of adenine–BH 3 complex: an investigation with density functional theory (DFT) method

Abstract

Geometries and binding energies are predicted at B3LYP/6-311+G* level. Single energy calculations using much larger basis sets (6-311+G(2df,p) and natural bonding analysis have also been carried out on the six optimized conformers. The analyses for the combining interaction between BH 3 and adenine with the theory of atom-in-molecules have been performed. The results indicate that the three conformers in which the pyridine-type nitrogen atoms offer their lone pair electrons to the empty p orbital of born atom are the most stable ones with the stabilization energies of 28.09, 27.77, 27.37 kcal/mol (with BSSE correction), respectively, while the conformers in which the pyrrole-type nitrogen atom or carbon atom offers π electron to the empty orbital of born atom are fairly unstable and the conformer with the nitrogen atom of amino group offer its lone pair electrons to boron has a intergrades stability.