Elucidating the mechanism of how we can achieve fine tuning of intermolecular interaction strength will be helpful for designing functionally important molecules. In the present study, a theoretical analysis is...

Elucidating how the halogen-bonding ability and strength are controlled by the substituent effect and how this control depends on halogen atom will be essential for finelytuned design of functionally important molecules. Here, this problem is tackled by analyzing the electron density differences/changes for variously substituted halobenzenes. It is shown that the anisotropy of the electron distribution around the halogen atom, which is an important factor for halogen-bonding ability, is not much affected by the substituent effect and rather simply depends on the halogen atom, while the partial charge on the halogen atom, which is related to the bond dipole of the CÀ X bond, is significantly modulated by the substituent effect and gives rise to enhancement of the electrostatic potential on the line extended from the CÀ X bond. The properties related to the polarization effect are also discussed.