The role of solvent on the base stacking properties of the stacked cytosine dimer

The role of solvent on the base stacking of cytosine dimers is analyzed with the help of the Onsager reaction field model in the framework of Hartree–Fock theory. In this Letter, it has been found that the total energy of the base stacked cytosine dimer depends on the twist angle. The inclusion of solvent in the calculation, destabilizes the parallelly stacked cytosine dimer (twist angle equals 0°) by ∼22.4 kcal/mol. The dipole moment of the anti-parallelly stacked cytosine dimer (twist angle equals 180°) is zero and hence, this conformer is not influenced by the presence of the solvent environment.