Protonated MF^– (M=Au, Ir, Os, Re, Ta, W) behave as superacids and are building blocks of new class of salt

Novel strong superacids HMF6 (M=Au, Ir, Os, Re, Ta, W) are proposed and are investigated with the help of DFT/B3LYP method and SDD basis set for 5d transition metals as well as 6-311++G (d) basis set for H and F atoms. These HMF6 superacids are composed with Brønsted/Lewis (MF5/HF). The stabilities of HMF6 are discussed with the help of structure, dissociation energy through HF channel, and normal mode analysis. The ΔEdisso>0 shows that all HMF6 superacids are energetically stable through HF dissociation channel. The gas phase acidity of HMF6 has been calculated by the Gibbs free deprotonation energy. All species of HMF6 belong to superacids having smaller deprotonation energy; 100% concentrated H2SO4 acids however predicted ΔGdep of HAuF6, is nearly equal to ΔGdep of HSbF6. The strength of acidity of HMF6 is closely related to vertical detachment energy (VDE) of their corresponding superhalogen anions MF6−. This study provide appropriate path to design new class of superacids which is more acidic than HSbF6. We have also modelled and discussed supersalt by the interaction of Li with MF6 superhalogen.