Detection of the intrinsic two energy gaps in individual Mn12 single molecule magnets

► Mn12-ac adsorbed on surfaces is investigated by microRaman spectrograph and STM/S. ► It is found that Mn12-ac molecules remain intact upon adsorbing on HOPG surfaces. ► STS curves within an isolated molecule reveal two energy gaps of 2.34 and 0.87 eV. ► The energy gaps can be interpreted according to the former theoretical calculation.