Properties of halogen bonds in FArCCX···HMY (X = Cl and Br; M = Be and Mg; Y = H, F, and CH3) complexes: An ab initio and topological analysis

The halogen-bonded complexes of FArCCX (X = Cl and Br) with HMY (M = Be and Mg; Y = H, F, and CH3) have been studied using ab initio calculations at the MP2/6-311++G(2d,2p) level. The results show that these complexes are stable by a halogen-hydride halogen bond. Its strength is comparable to that of dihydrogen bond and weaker than conventional halogen bond. The properties of FCCX (X = Cl and Br) suffer a big change when an Ar atom is inserted into this molecule. The F atom in the HMF makes the complex less stable, whereas the methyl group in the HMCH3 causes the complex more stable. An analysis of atoms in molecules (AIM) has also been performed for these complexes.