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Consistent van der Waals radii for the whole main group
Manjeera Mantina1, Adam C Chamberlin, Rosendo Valero
1Department of Chemistry and Supercomputing Institute, University of Minnesota, Minneapolis, Minnesota 55455-0431, USA.
The Journal of Physical Chemistry. A
|April 23, 2009
Summary
This study introduces new atomic radii for 16 main-group elements, extending the widely used Bondi scale. These values are crucial for accurate molecular modeling and understanding chemical interactions.
Area of Science:
- Chemistry
- Physical Chemistry
- Computational Chemistry
Background:
- Atomic radii are essential for molecular modeling but values are missing for some elements.
- Bondi's van der Waals radii are widely used but incomplete for main-group elements.
- Accurate atomic radii are critical for predicting molecular structure and interactions.
Purpose of the Study:
- To determine and present new atomic radii for 16 main-group elements.
- To ensure compatibility with the established Bondi scale of atomic radii.
- To enhance the predictive power of molecular modeling and chemical interaction studies.
Main Methods:
- Utilized relativistic coupled-cluster electronic structure calculations to determine repulsive-wall distances.
- Developed two-parameter correlations between calculated distances and existing Bondi radii.
- Applied these correlations to derive new atomic radii for underrepresented elements.
Main Results:
- Presented new atomic radii values for 16 main-group elements (Be, B, Al, Ca, Ge, Rb, Sr, Sb, Cs, Ba, Bi, Po, At, Rn, Fr, Ra).
- The determined radii are designed to be consistent with Bondi's established scale.
- New radii values range from 1.53 Å (Be) to 3.48 Å (Fr).
Conclusions:
- The newly determined atomic radii fill critical gaps in the existing data.
- These enhanced atomic radii facilitate more comprehensive molecular modeling.
- The findings contribute to a more accurate understanding of chemical bonding and interactions.
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