Abstract
Electronegativity is a fundamental concept in chemistry. Despite its importance, the experimental determination has been limited only to ensemble-averaged techniques. Here, we report a methodology to evaluate the electronegativity of individual surface atoms by atomic force microscopy. By measuring bond energies on the surface atoms using different tips, we find characteristic linear relations between the bond energies of different chemical species. We show that the linear relation can be rationalized by Pauling’s equation for polar covalent bonds. This opens the possibility to characterize the electronegativity of individual surface atoms. Moreover, we demonstrate that the method is sensitive to variation of the electronegativity of given atomic species on a surface due to different chemical environments. Our findings open up ways of analysing surface chemical reactivity at the atomic scale.
Highlights
Electronegativity is a fundamental concept in chemistry
Pauling’s electronegativity values for individual single atoms on surfaces can be estimated using site-specific energy spectroscopy acquired with a variety of atomic force microscopy (AFM) tips
We show that the binding energies for individual surface atoms observed using different tips can provide an ensemble of data that can be used later to determine the electronegativity of different chemical elements or chemical groups on a surface (Fig. 1a)
Summary
Electronegativity is a fundamental concept in chemistry. Despite its importance, the experimental determination has been limited only to ensemble-averaged techniques. Pauling’s electronegativity values for individual single atoms on surfaces can be estimated using site-specific energy spectroscopy acquired with a variety of AFM tips.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have