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El carbono tetracoordinado plano en sistemas extendidos.
Pattath D Pancharatna1, Miguel Angel Méndez-Rojas, Gabriel Merino
1Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, USA.
Journal of the American Chemical Society
|November 19, 2004
Resumen
Los investigadores exploraron la extensión de un nuevo sistema de carbono, C(5)(2-), en polímeros. Descubrieron que se favorece la coordinación a través de los carbonos terminales, lo que lleva a nuevos materiales potenciales como C(5) M(x).
Área de la Ciencia:
- Química teórica es la química teórica.
- Ciencia de los materiales Ciencia de los materiales.
- Química del estado sólido.
Sus antecedentes:
- Se ha propuesto un nuevo sistema de carbono tetracoordinado plano, C(5)(2-).
- Esta estructura única ofrece potencial para la extensión en redes extendidas.
Objetivo del estudio:
- Investigar el potencial para extender la unidad C(5)(2-) en sistemas de una, dos y tres dimensiones.
- Para explorar la polimerización de C(5)(2-) en presencia de contracations.
Principales métodos:
- Análisis de la estructura electrónica de C(5)(2-).
- Examen computacional y optimización de la geometría de los dímeros (por ejemplo, C{10}Li{3}-), C{10}Li{4}) y los trímeres (C{15}Li{6}).
- Cálculos de la estructura de la banda y evaluaciones energéticas para sistemas poliméricos potenciales.
Principales resultados:
- La coordinación a través de los carbonos terminales se identifica como el modo preferido en oligómeros y polímeros.
- Se identificaron varias estequiometrías plausibles para los sistemas C(5) M(x) (donde M = Li, Be, Pt, Zn).
- Se evaluó la racionalidad electrónica y estructural de estos materiales poliméricos potenciales.
Conclusiones:
- La unidad C(5)(2-) se puede extender a estructuras poliméricas.
- El estudio proporciona una base para el diseño de nuevos materiales basados en carbono con propiedades electrónicas sintonizables.
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