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Published on: May 20, 2019
Analysis of polyaddition levels in i-Sc3NC80
Josep M Campanera1, Malcolm I Heggie, Roger Taylor
1Departament de Química Física i Inorgànica, Universitat Rovira i Virgili, 43005 Tarragona, Catalonia, Spain.
The Journal of Physical Chemistry. B
|July 21, 2006
Summary
Highly hydrogenated and fluorinated fullerene cages, including those with Sc3N molecules, show stable structures with specific ring formations. Hydrogenation of Sc3N-containing fullerenes is more challenging than for empty ones.
Area of Science:
- Computational Chemistry
- Materials Science
- Nanotechnology
Background:
- Fullerenes are allotropes of carbon with unique cage-like structures.
- Functionalization of fullerenes with hydrogen and fluorine can significantly alter their properties.
- Scandium nitride (Sc3N) clusters encapsulated within fullerenes offer novel electronic and structural characteristics.
Purpose of the Study:
- To investigate the stability and structural properties of highly hydrogenated and fluorinated endohedral fullerenes, specifically i-Sc3NC80.
- To determine the most stable isomers for various degrees of hydrogenation and fluorination.
- To compare the stability of functionalized i-Sc3NC80 with empty C80 fullerenes.
Main Methods:
- Density Functional Theory (DFT) calculations were employed to model the electronic and structural properties.
- Calculations focused on determining the relative stabilities of different isomers based on atom addition.
- Geometrical analysis was performed to understand the impact of functionalization on the fullerene cage and encapsulated molecule.
Main Results:
- Addition of 44 atoms to i-Sc3NC80 favors structures with six octahedrally located benzenoid rings.
- Structures with up to 52 added atoms are stabilized by four benzenoid rings, consistent with fluorination data.
- Hydrogenation of i-Sc3NC80 is computationally more difficult than for empty C80.
- The Sc3N molecule transitions from planar in the parent fullerene to pyramidal in some functionalized derivatives.
Conclusions:
- Highly hydrogenated and fluorinated i-Sc3NC80 fullerenes exhibit distinct stable structures dictated by benzenoid ring formation.
- The encapsulation of Sc3N influences the stability and structural dynamics of functionalized fullerene cages.
- Orbital interactions and localized double bonds play a crucial role in stabilizing functionalized endohedral fullerenes.
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