Electronegativity determination of individual surface atoms by atomic force microscopy

Area of Science:

• Surface Science
• Chemical Physics
• Atomic Force Microscopy

Background:

• Electronegativity is crucial in chemistry but traditionally measured via ensemble-averaged techniques.
• Experimental determination of individual atom electronegativity has been a significant challenge.

Purpose of the Study:

• To introduce a novel methodology for evaluating the electronegativity of individual surface atoms.
• To demonstrate the sensitivity of this method to variations in chemical environments.

Main Methods:

• Utilizing atomic force microscopy (AFM) to measure bond energies on individual surface atoms.
• Employing different AFM tips to probe varying chemical species.
• Analyzing linear relationships between measured bond energies.

Main Results:

• A characteristic linear relationship was observed between bond energies of different chemical species.
• This linear relationship aligns with Pauling's equation for polar covalent bonds.
• The method successfully detected variations in electronegativity due to different surface chemical environments.

Conclusions:

• The developed AFM methodology enables the characterization of individual surface atom electronegativity.
• This technique provides a new pathway for analyzing surface chemical reactivity at the atomic scale.
• Findings offer insights into the localized electronic properties of surface atoms.