The Lewis-acid behavior of [SF3][MF6] (M = Sb, As) salts toward mono- and bidentate nitrogen bases was explored. Reactions of [SF3][MF6] with excesses of CH3CN and C5H5N yielded [SF3(L)(2)](+) (L = CH3CN, C5H5N) salts, whereas the reaction of [SF3][SbF6] with equimolar 1,10-phenanthroline (phen) in CH3CN afforded [SF3(phen)][SbF6]center dot 2CH(3)CN. Salts of these cations were characterized by low-temperature X-ray crystallography and Raman spectroscopy in the solid state as well as by F-19 NMR spectroscopy in solution. In the solid state, the geometries of [SF3(NC5H5)(2)](+) and [SF3(phen)](+) are square pyramids with negligible cation-anion contacts, whereas the coordination of CH3CN and [SbF6](-) to [SF3](+) in [SF3(NCCH3)(2)][SbF6] results in a distorted octahedral coordination sphere with a minimal perturbation of the trigonal-pyramidal SF3 moiety. F-19 NMR spectroscopy revealed that [SF3(L)(2)](+) is fluxional in excess L at -30 degrees C, whereas [SF3(phen)](+) is rigid in CH2Cl2 at -40 degrees C. Density functional theory (DFT-B3LYP) calculations suggest that the S-N bonds in [SF3(NC5H5)(2)](+) and [SF3(phen)](+) possess substantial covalent character and result in a regular AX(5)E VSEPR geometry, whereas those in [SF3(NCCH3)(2)](+) are best described as S center dot center dot center dot N chalcogen-bonding interactions via sigma-sholes on [SF3](+), which is consistent with the crystallographic data.