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B22- y B23-: todos los análogos de boro del antraceno y el fenantreno
Alina P Sergeeva1, Zachary A Piazza, Constantin Romanescu
1Department of Chemistry and Biochemistry, Utah State University, Logan, Utah 84322, USA.
Journal of the American Chemical Society
|October 4, 2012
Resumen
Los grandes cúmulos de boro B(22)(-) y B(23)(-) revelan sorprendentes estructuras planas y enlaces. Estos grupos de boro imitan a los hidrocarburos aromáticos policíclicos como el antraceno y el fenantreno.
Área de la Ciencia:
- Química Física es la química física.
- Ciencia de los materiales Ciencia de los materiales.
- Nanotecnología La nanotecnología es la nanotecnología.
Sus antecedentes:
- Los grupos de boro exhiben estructuras únicas dependientes del tamaño y la unión.
- Comprender estas propiedades es clave para desarrollar nuevas nanoestructuras basadas en boro.
Objetivo del estudio:
- Para investigar las estructuras y los enlaces químicos de los grupos de boro de 22 y 23 átomos.
- Para comparar sus propiedades con el boro a granel y los análogos moleculares conocidos.
Principales métodos:
- Espectroscopia combinada de fotoelectrones y cálculos ab initio.
- Análisis de la estructura electrónica y la unión química.
Principales resultados:
- B(22)(-) exhibe una rejilla triangular casi plana, ligeramente curvada.
- B(23)(-) forma un cúmulo perfectamente plano, en forma de corazón, con una cavidad pentagonal.
- Ambos grupos muestran sistemas de electrones π deslocalizados análogos a los hidrocarburos aromáticos policíclicos.
Conclusiones:
- Los mayores grupos de boro negativo experimentalmente caracterizados, B(22)(-) y B(23)(-), sirven como análogos de todo el boro del antraceno y el fenantreno.
- Los cúmulos de boro pueden mantener la planaridad a grandes tamaños, exhibiendo nuevos patrones de enlace.
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