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Trastorno de orientación en sólidos libres de disolventes c70
Science (New York, N.Y.)
|November 29, 1991
Resumen
Se analizaron las estructuras de alta temperatura C ((70)). Las muestras libres de disolventes forman cristales cúbicos centrados en la cara, mientras que las muestras que contienen disolventes forman cristales hexagonales apretados, revelando comportamientos estructurales distintos.
Área de la Ciencia:
- Química del estado sólido.
- Ciencia de los materiales ciencia de los materiales.
- La cristalografía es una técnica de cristalografía.
Sus antecedentes:
- Los fullerenos, como el C70 exhiben comportamientos estructurales complejos influenciados por las condiciones de procesamiento.
- Comprender las fases de alta temperatura de los fullerenos es crucial para su aplicación en la ciencia de los materiales.
Objetivo del estudio:
- Para determinar la estructura cristalina de alta temperatura de C libre de disolventes (70).
- Para comparar las estructuras de C ((70) preparado con y sin disolvente residual.
Principales métodos:
- Difracción de rayos X de polvo de difracción de alta resolución.
- Microscopía electrónica con microscopía electrónica.
- La cristalización a partir de una solución.
- La sublimación es la sublimación.
Principales resultados:
- El C ((70) libre de solventes forma principalmente cristales cúbicos centrados en la cara con fallas de apilamiento.
- C(70) cristalizado de la solución contiene tolueno residual y forma cristales hexagonales estrechamente empaquetados.
- El recocido reduce la fase hexagonal en muestras libres de disolventes.
- Ambas fases exhiben un trastorno de orientación completo.
Conclusiones:
- La presencia de disolvente tiene un impacto significativo en la estructura cristalina de alta temperatura del C70).
- El cúbico centrado en la cara es la fase de alta temperatura dominante para el C puro (70).
- Las fallas de apilamiento son una característica notable de la fase cúbica.
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