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Estructuras electrónicas y características energéticas de los nanotubos de carbono de pared única [5,5] y [9,0]
Jerzy Cioslowski1, Niny Rao, David Moncrieff
1Department of Chemistry and Biochemistry and School of Computational Science & Information Technology, Florida State University, Tallahassee, Florida 32306, USA. jerzy@kyoko.chem.fsu.edu
Journal of the American Chemical Society
|July 11, 2002
Resumen
Este estudio calculó las propiedades de los nanotubos de carbono de pared única de longitud finita (SWNT). Las propiedades de SWNT dependen de la longitud, la orientación de la tapa y exhiben una convergencia lenta con el tamaño.
Área de la Ciencia:
- Química computacional es la química computacional.
- Ciencia de los materiales Ciencia de los materiales.
- Nanotecnología La nanotecnología es la nanotecnología.
Sus antecedentes:
- Los nanotubos de carbono de pared única (SWNT) poseen propiedades electrónicas y estructurales únicas.
- Comprender estas propiedades es crucial para el diseño de nanomateriales avanzados.
Objetivo del estudio:
- Para calcular las propiedades termodinámicas y electrónicas clave de sillas de longitud finita y SWNT en zigzag.
- Para investigar la influencia de la longitud del tubo y la orientación de la tapa en las características de SWNT.
Principales métodos:
- Cálculos de la Teoría Funcional de Densidad (DFT) utilizando el nivel teórico B3LYP/6-311G*.
- Cálculo de las entalpias estándar de formación, potenciales de ionización, afinidades de electrones y brechas de banda.
Principales resultados:
- Las propiedades de SWNT son muy sensibles a la longitud del tubo y la orientación de la tapa (para SWNT en zigzag).
- Los SWNT de sillón de longitud finita muestran un comportamiento oscilatorio dependiente del tamaño, lo que refleja el carácter metálico.
- Se predice que los SWNT en zigzag serán semiconductores, independientemente de las tapas.
Conclusiones:
- Las propiedades de SWNT convergen lentamente con el aumento de la longitud del tubo.
- Se observan pequeñas distorsiones radiales a lo largo de los ejes SWNT.
- El estudio proporciona información valiosa sobre el tamaño y la dependencia estructural de las propiedades SWNT.
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