Exploring the simultaneous σ-hole/π-hole bonding characteristics of a Br•••π interaction in an ebselen derivative via experimental and theoretical electron-density analysis

In this study, the nature and characteristics of a short Br center dot center dot center dot pi interaction observed in an ebselen derivative, 2-(2-bromophenyl)benzo[d][1,2]selenazol-3(2H)-one, has been explored. The electronic nature of this Br center dot center dot center dot pi interaction was investigated via high-resolution X-ray diffraction and periodic density functional theory calculations using atoms-in-molecules (AIM) analysis. This study unravels the simultaneous presence of sigma-hole and pi-hole bonding characteristics in the same interaction. The dual characteristics of this unique Br center dot center dot center dot pi interaction are further established via molecular electrostatic potentials (MESPs) and natural bond orbitals (NBOs).