[14a-A32-1~7] 6.6 Probe Microscopy

△ [14a-A32-5] Electronegativity of Single Atoms Determined by Atomic Force Microscopy

〇(PC)Jo Onoda^1,2, Martin Ondracek³, Pavel Jelinek³, Yoshiaki Sugimoto^1,2 (1.Univ. of Tokyo, 2.Osaka Univ., 3.ASCR)

Keywords:atomic force microscopy, electronegativity

Electronegativity, an important theoretical concept in chemistry, was originally defined by Linus Pauling in 1932. Conventional experimental means for measuring electronegativity have been limited to thermochemical techniques, i.e., the measurement of ensemble-averaged bond energies. Here, we introduce a new methodology to evaluate the electronegativity of individual surface atoms by atomic force microscopy (AFM). By measuring bond energies on surface atoms using different tips, we found characteristic linear relations between the bond energies of different chemical species. We interpreted the linear relations based on Pauling’s equation for polar covalent bond. Using the intercepts, we successfully quantify electronegativity values for various elements. These findings demonstrate that AFM has the ability to measure the electronegativity of individual surface atoms.