Amphiphilic organic single crystals of stearic acid of B- and C-types, sodium dodecylsulfate (SDS) and dodecyltrimethylammonium bromide (DTAB) were observed by AFM. The exposed methyl groups for stearic acid and SDS, and trimethylammonium group for DTAB were imaged as circular formed peaks, but more detailed structure of these groups were not defined. Since the image of the cleavaged surface of stearic acid was easily and reproducibly observed, this will be useful for standard sample of AFM for alkyl organic compounds.
