Theoretical study of F−–(H2)n and Cl−–(H2)n (n = 1–8) anion complexes

In the present study, the structural and bonding properties of F−–(H2)n and Cl−–(H2)n (n = 1–8) anion complexes have been investigated by quantum chemical calculations at the MP2/aug-cc-pVTZ level. The computations gave different global minimum structures for most of the F−–(H2)n and Cl−–(H2)n complexes. The strength of the F−–H2 interaction depends strongly, while that of the Cl−–H2 one only marginally on the number of H2 ligands. Our NBO analysis revealed a considerable charge transfer from the halide ion to the σ∗(H2) orbital.