To quantify and validate the presence of non-covalent interactions (NCIs) within Pathway 1 of the halide abstraction reaction catalysed by XB-donors CAT3 and CAT9, computational methods QTAIM and NBO were employed. The key parameters of interest were the electron density at the critical bond point (ρ BCP ) and the CT, associated with the substrate-catalyst stabilisation interaction, as illustrated in Figure . Table highlights the ρ BCP for the Br•••I interaction within the CAT3 and CAT9 catalysed reaction pathway 1, which generally indicates a consistent noncovalent nature, representative of halogen bonding between the catalyst and substrate. The characterisation of CT upon complexation from the lone pair of electrons LP (Br) of the substrate and the non-bonding orbital of the catalyst BD* (C-I) was in agreement with the aforementioned QTAIM analysis (Table ). Based on the similar catalytic activity reported for the halide abstraction reaction under the catalysis of both CAT3 and CAT9, the data of ρ BCP and E(2) implies that the monodentate XB substrate stabilisation interaction, as seen for CAT9, is equivalent in efficiency to the bidentate XB interaction via CAT3. Despite the contrasting binding modes of these two catalytic systems, their catalytic performance appears to be comparable, indicating that depending on the specific catalytic scaffolding, both the monodentate and bidentate binding modes can effectively facilitate the halide abstraction.