Ab initio investigations on non-metallic chain-shaped FnHn+1+ series of superalkali cations

Abstract

FnHn+1+ cations (n = 1–10) have been systematically explored using ab initio MP2/6-311++G(d,p) and molecular dynamics methods. These cations possess chain-like geometrical structures comprised of the FH2 or F2H3 cores in dependence on the n parity. Ab initio molecular dynamics, as well as deprotonation and HF-reduction energies, suggest the stability of these cations. FnHn+1+ cations exhibit superalkali nature for n > 1, as their vertical electron affinity decays exponentially from 4.48 eV to 1.60 eV as n increases from 2 to 10. This study offers new insights into the protonated HF clusters and demands further explorations in this direction.