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Compuestos de racimo de alcanetiolato de oro ubicuo de 8 y 29 kDa: determinación espectrométrica de masas de fórmulas

Nirmalya K Chaki¹, Yuichi Negishi, Hironori Tsunoyama

¹Department of Materials Molecular Science, Institute for Molecular Science, Myodaiji, Okazaki 444-8585, Japan.

Journal of the American Chemical Society

|June 13, 2008

Resumen

Los investigadores identificaron las fórmulas moleculares precisas para los racimos de oro [Au38(SCn) 24]z y [Au144 ((SCn) 59]z. Su estabilidad está vinculada a factores geométricos y motivos comunes de interfaz de Au-tiolato.

Área de la Ciencia:

Nanotecnología La nanotecnología es la nanotecnología.
Ciencia de los materiales Ciencia de los materiales.
Química Química es la química.

Sus antecedentes:

Los clústeres de oro protegidos por alcanetiolato son cruciales en la nanotecnología.
Comprender su estructura y estabilidad es clave para las aplicaciones.
Estudios anteriores han caracterizado grupos de oro más pequeños.

Objetivo del estudio:

Para determinar las fórmulas moleculares y los estados de carga de los cúmulos de oro de 8 y 29 kDa.
Proponer posibles estructuras geométricas para estos grupos.
Para aclarar los factores que contribuyen a su estabilidad y motivos de interfaz.

Principales métodos:

Se utilizó la espectrometría de masas de ionización por electrospray (ESI-MS).
El análisis se centró en los clusters de oro ubicuos protegidos por alcanetiolato.
Comparación con estructuras experimentales y teóricas recientemente determinadas.

Principales resultados:

El cúmulo de 8 kDa fue identificado como [Au38(SCn) 24]z.
El cúmulo de 29 kDa fue identificado como [Au144(SCn) 59]z.
Ambas especies exhiben estados de carga de z >= 0.

Conclusiones:

Los factores geométricos contribuyen a la alta estabilidad de estos grupos de oro.
La interfaz oro-tiolato exhibe motivos comunes independientemente de la estructura del núcleo.
Estos hallazgos avanzan en la comprensión de la formación y la estabilidad de los cúmulos de oro.

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