Magnetic properties of oriented Mn12 Pivalates16 (Mn12Piv16) single molecule crystals have been studied. Steps in the hysteresis loops, which are characteristic of quantum tunneling of magnetization, are observed at regular intervals of the magnetic field. Self-assembling of monolayers of this molecular material on a surface is then achieved. A process is described by which Mn12Piv16 clusters are grafted onto the crystalline Au(111) surface by means of organosulfur SH–(CH2)10–COOH ligands in order to hold them firmly. This self-assembled monolayer was then characterized by Scanning tunneling microscopy and X-ray photoelectron spectroscopy so as to provide the topographic structure, the quality, and the stability during annealing to high temperature. © 2004 American Institute of Physics.