Fig. 4: DFT calculated structure and charge transfer of a halobenzene Br∙∙∙Br∙∙∙I windmill on Cu(111).
From: Surface-controlled reversal of the selectivity of halogen bonds
a Top view of DFT calculated windmill structure consisting of two bromobenzenes and one iodobenzene on Cu(111) revealing the adsorption positions of the molecules. The \(\left[ {11\bar 2} \right]\) direction is indicated by the blue arrow. b Bonding angles and distances of structure in (a). The effective bonding angles of the three halogen bonds are 118°, 119°, and 123°, respectively. c Side view of (a). Blue arrows indicate the distance between the halogens and the Cu(111) surface plane. d Differential charge density at the 10−4 e bohr−3 isosurface (yellow = charge accumulation, blue = charge depletion). Due to the interaction with the Cu(111) surface, charge is depleted from the negative belts (blue regions) and accumulated at the σ-holes (yellow regions). For iodine this effect is much stronger than for bromine. e AFM constant height image of a Br···Br···I windmill structure of IparaBrmeta-TP on Cu(111) (see details in Fig. S3). f Simulated force map for the structure in (a).
