Comprehensive theoretical study of all 1812 C60 isomers
Rebecca Sure1, Andreas Hansen, Peter Schwerdtfeger
1Mulliken Center for Theoretical Chemistry, Institut für Physikalische und Theoretische Chemie, Universität Bonn, Beringstr. 4, 53115 Bonn, Germany. grimme@thch.uni-bonn.de.
Physical Chemistry Chemical Physics : PCCP
|May 25, 2017
Summary
This study explores 1812 fullerene C60 isomers using quantum chemistry, revealing energy distributions and stability factors. Findings offer insights for modeling larger carbon nanostructures and analyzing C80 isomers.
Area of Science:
- Computational chemistry
- Materials science
- Nanotechnology
Background:
- Fullerenes, like C60, are carbon allotropes with diverse isomeric structures.
- Understanding fullerene isomer stability is crucial for their application in materials science.
Purpose of the Study:
- To investigate all 1812 isomers of fullerene C60.
- To determine the relative energy distribution and rationalize the stability of these isomers.
- To provide methodological insights for modeling larger carbon nanostructures.
Main Methods:
- High-accuracy quantum chemistry methods were employed for optimization and energy calculations.
- Density Functional Theory (DFT) at the PBE-D3/def2-TZVP and PW6B95-D3ATM/def2-QZVP levels were used.
- Results were validated against coupled-cluster calculations (DLPNO-CCSD(T)/CBS*) and semiempirical methods were benchmarked.
Main Results:
- Reliable relative energy distributions for 1812 C60 isomers were obtained for the first time.
- A significant number of isomers (1267) fall within an energy window of 150-250 kcal mol-1.
- Isomer stability correlates with a small pentagon signature, large volume, and spherical cage structure, extending beyond the isolated pentagon rule.
Conclusions:
- The study provides a comprehensive energetic map of C60 isomers.
- Key structural and electronic factors governing fullerene isomer stability were identified.
- The best semiempirical method was successfully applied to analyze the 31,924 isomers of C80.
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