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Síntesis del carbono acetilénico lineal: el carbono alotrópico "sp" del carbono
Science (New York, N.Y.)
|January 20, 1995
Resumen
Los investigadores sintetizaron un nuevo alotrópico de carbono con enlaces triples y simples alternados. Este material de carbono lineal, estabilizado por tapas de extremo, muestra una notable estabilidad térmica y potencial para nuevas aplicaciones de materiales.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- Química Química es la química.
- Nanotecnología La nanotecnología es la nanotecnología.
Sus antecedentes:
- Los alotrópicos de carbono, como los fullerenos, se estudian extensamente.
- Las cadenas de carbono lineales con hibridación sp se proponen teóricamente, pero son experimentalmente difíciles de sintetizar y estabilizar.
Objetivo del estudio:
- Sintetizar y caracterizar un nuevo alotrópico lineal de carbono con enlaces triples y simples alternados.
- Para investigar la estabilidad y las propiedades de estas especies de carbono acetilenico.
Principales métodos:
- Síntesis de pequeños compuestos modelo de carbono acetilenico (8-28 átomos de carbono) con grupos estabilizadores terminales.
- Utilizando técnicas basadas en láser, similares a la generación de fullereno, para producir especies de carbono acetilenico de cadena más larga.
- Caracterización de los alotrópicos de carbono sintetizados.
Principales resultados:
- Los pequeños compuestos de carbono acetilénico con grupos terminales (ter-butilo, trifluorometilo) exhiben estabilidad entre 130-140°C.
- La síntesis a base de láser con grupos de tapa de extremo produce especies de carbono acetilenico térmicamente estables que superan los 300 átomos de carbono.
- Estas especies están cubiertas con grupos trifluorometilo o nitrilo, con una formación insignificante de fullereno.
- Los compuestos de carbono acetilénico sintetizados muestran una sensibilidad moderada a la luz, pero no son muy sensibles a la humedad o al oxígeno.
Conclusiones:
- Se ha sintetizado con éxito un alotróp de carbono estable y lineal basado en la hibridación sp y en la alternancia de enlaces triples/singles.
- Los grupos de tapa final son cruciales para estabilizar estas cadenas de carbono acetilenos contra reacciones posteriores.
- La síntesis basada en láser ofrece una ruta viable para producir materiales de carbono acetilenico de cadena larga, distintos de la producción de fullereno.
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