Some properties of molybdenite cleavage surfaces

Low energy electron diffraction, Auger electron spectroscopy and photoemission studies have been carried out on surfaces of molybdenite prepared by cleavage. Surfaces cleaved in ultra high vacuum are extremely inert. There is some evidence that surfaces containing adsorbed oxygen have a weak affinity for water vapour and the significance of the result for some of the mechanical properties of MoS 2 is discussed. Low energy electron diffraction measurements are consistent with a surface structure not differing greatly from that of the bulk, and the energy analysis of back scattered electrons confirms the existence of two valence bands in MoS 2 .