Ozone addition to C60 and C70 fullerenes: a DFT study
D Sh Sabirov1, S L Khursan, R G Bulgakov
1Physical Chemistry Problems Laboratory, Institute of Petrochemistry and Catalysis RAS, Ufa 450075, Russia.
Journal of Molecular Graphics & Modelling
|May 6, 2008
Summary
Density functional theory calculations reveal that ozone addition to C(60) fullerenes preferentially occurs via [6.6]-addition. This reaction pathway is energetically favorable and proceeds without a barrier, aligning with experimental findings for ozone and C(60) interactions.
Area of Science:
- Computational chemistry
- Physical organic chemistry
- Materials science
Background:
- Fullerenes, such as C(60) and C(70), are allotropes of carbon with unique electronic and structural properties.
- Ozone (O(3)) is a powerful oxidizing agent capable of reacting with various organic molecules.
- Understanding the reaction mechanisms between fullerenes and ozone is crucial for potential applications in materials functionalization and chemical synthesis.
Purpose of the Study:
- To investigate the preferred modes of synchronous ozone addition to C(60) and C(70) fullerenes.
- To determine the energetic favorability and activation barriers for different addition pathways.
- To compare theoretical calculations with experimental data for the ozone-C(60) reaction.
Main Methods:
- Density functional theory (DFT) calculations were employed to model the reaction pathways.
- Analysis of activation enthalpies was performed to identify the most favorable reaction modes.
- Rate constants were calculated for specific addition reactions and compared to experimental values.
Main Results:
- For C(60) fullerene, [6.6]-addition of ozone is the most energetically favorable pathway and occurs without a significant activation barrier.
- For C(70) fullerene, ozone addition to ab- and cc-bonds were found to be the most favorable.
- The theoretical calculation for the rate constant of [6.6]-addition to C(60) closely matched the experimental value.
Conclusions:
- The [6.6]-addition pathway is the dominant and most facile route for ozone addition to C(60).
- Ozone addition to C(70) exhibits a preference for ab- and cc-bonds.
- The theoretical model accurately predicts the kinetics of ozone addition to C(60) fullerenes.
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