Theoretical interpretation of scanning tunneling microscopy images: Application to the molybdenum disulfide family of transition metal dichalcogenides

We have performed ab initio quantum mechanical calculations to describe scanning tunneling microscopy (STM) images of MoS_2 and MoTe_2. These results indicate that the interpretation of the STM images of these and related materials depends sensitively on experimental conditions. For example, determining whether the maximum tunneling current correlates to the top atom (S or Te) or to the second‐layer atom (Mo) requires information on the tip‐sample separation. Based on these results we discuss some STM experimental procedures which would allow assignment of the chemical identity of STM spots with greater certainty