A molecular electrostatic potential bond critical point model for atomic and group electronegativities

Area of Science:

• Quantum Chemistry
• Physical Chemistry
• Periodic Trends

Background:

• Electronegativity is a fundamental chemical property influencing molecular behavior.
• Existing electronegativity scales show variations, particularly for transition elements.
• A consistent and accurate scale is crucial for predictive chemistry.

Purpose of the Study:

• To develop a novel, consistent scale for atomic electronegativities.
• To accurately determine electronegativities for main block and d-block transition elements.
• To evaluate group electronegativities using a unified methodology.

Main Methods:

• Utilizing the molecular electrostatic potential (MEP) at the bond critical point of C-E bonds in methyl-element-hydride systems (H(3)C-EH(n)).
• Analyzing the position and value of the MEP bond critical point to derive electronegativity values.
• Extending the method to calculate group electronegativities by substituting hydrogens with other groups.

Main Results:

• A new, consistent scale of atomic electronegativities was established for main block and d-block elements.
• The derived scale demonstrates strong agreement with established scales like Pauling and Mulliken, especially for main block elements.
• The new scale is anticipated to offer improved accuracy for transition element electronegativities due to a more rigorous approach.
• Evaluated group electronegativities show good correlation with the Inamoto and Mullay scales.

Conclusions:

• The MEP-based method provides a reliable and consistent approach to determining atomic and group electronegativities.
• This new scale offers a valuable tool for understanding and predicting chemical properties, particularly for transition metals.
• The consistent methodology enhances the accuracy and applicability of electronegativity scales in chemical research.