The activity of F- is an important factor in the design of both inorganic and organic reactions involving fluorine compounds. The present study investigates interactions of F- with diols in alkali-metal fluoride-diol complexes. Increases in the reactivities of alkali-metal fluorides and their solubilities in alcohols is observed with increasing cation size. The difference in alkali-metal ion size produces different structural motifs for F--diol complex salts. The CsF complex salt with ethylene glycol (EG), CsF-EG, has a layered structure, whereas the Rb and K complex salts, (RbF)(5)-(EG)(4) and (KF)(5)-(EG)(4), form columnar structures. Comparison of the CsF complex salts with three different diols- EG, 1,3-propylene glycol (PG(13)), and 1,4-butylene glycol (PG(14))-revealed that the diol chain length affects the bridging mode in their layered structures. EG bridges two OH oxygen atoms within the same CsF layer in CsF-EG, whereas PG(13) and BG(14) bridge two OH oxygen atoms in different CsF layers in (CsF)(2)-PG(13) and CsF-BG(14), respectively. The F(-)ion coordination environment involves interactions between alkali-metal ions and H atom(s) in the diol OH groups, where the F-center dot center dot center dot H interactions are more dominant than the F-center dot center dot center dot M+ interaction, based on Hirshfeld surface analyses. The O-H bond weakening observed by infrared spectroscopy also reflects the strengths of the F-center dot center dot center dot H interactions in these complex salts.