Imaging nano-domains in spin crossover (SCO) compounds remains so far an unreached goal. We report on the first AFM tapping-mode investigation of SCO single crystals, performed at room temperature with the well known mononuclear compound [Fe(ptz) 6](BF 4) 2 (ptz=1-propyl- tetrazole) and the trinuclear supramolecular compound [Fe 3 (hyetrz) 6 (H 2O) 6](CF 3SO 3) 6 (hyetrz=4-(20-hydroxyethyl)-1,2,4-triazole) which shows a gradual spin conversion centred at room temperature. The natural surface of the former crystal revealed a volatile coating of the scanned area attributed to the transport of adsorbed water under the effect of interaction with theAFMtip. The second one showed astonishing leopard-skin patterns assigned to the effect of atmospheric humidity on this hygroscopic compound. Their origin is discussed. We suggest the use of fluid coating layers as a general method for revealing the nano-patterning of physical properties (e.g. like-spin domains) at the surface of dielectric materials. Image Presented AFM-tapping images of [Fe 3 (hyetrz) 6 (H 2O) 6](CF 3SO 3) 6 at room temperature and ambient atmosphere. Copyright © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.