Various anions were surrounded by n molecules of CF 3 H, which was used as a prototype
CH donor solvent, and the structures and energies studied by M06-2X calculations with a 6-
31+ G∗∗ basis set. Anions considered included the halides F−, Cl−, Br− and I−, as well as
those with multiple proton acceptor sites: CN−, NO 3−, HCOO−, CH 3 COO−, HSO 4−, H 2
PO 4−, and anions with higher charges SO 4 2−, HPO 4 2− and PO 4 3−. Well structured
cages were formed and the average H-bond energy decreases steadily as the number of …