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Reconstitution of Basic Mitotic Spindles in Spherical Emulsion Droplets
Published on: August 13, 2016
Mecanismo molecular para la nucleación cruzada entre polimorfos.
Caroline Desgranges1, Jerome Delhommelle
1Department of Chemical Engineering, University of South Carolina, 301 South Main Street, Columbia, South Carolina 29201, USA.
Journal of the American Chemical Society
|August 10, 2006
Resumen
El polimorfismo concomitante surge de la nucleación cruzada, donde una forma cristalina crece sobre otra. Este proceso selectivo ocurre entre polimorfos con energías libres similares, ofreciendo nuevos conocimientos sobre los mecanismos de cristalización.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- Química computacional es la química computacional.
- Física Química Física Química es la física de la química.
Sus antecedentes:
- Los líquidos súper enfriados pueden cristalizarse en múltiples formas estructurales (polimorfas).
- Comprender los mecanismos que rigen la selección de polimorfos es crucial para controlar las propiedades de los materiales.
Objetivo del estudio:
- Para investigar las primeras etapas de la cristalización en líquidos superenfriados de Lennard-Jones.
- Para dilucidar los mecanismos moleculares detrás del polimorfismo y la nucleación cruzada concomitantes.
Principales métodos:
- Simulaciones moleculares de los sistemas de partículas Lennard-Jones.
- Análisis de los procesos de nucleación y crecimiento.
Principales resultados:
- Se observó la aparición de polimorfismo concomitante.
- Se demostró que la nucleación cruzada de un polimorfo metastable en un polimorfo estable impulsa este fenómeno.
- Se demostró que la nucleación cruzada es selectiva, ocurriendo solo entre polimorfos con energías libres similares.
Conclusiones:
- La nucleación cruzada es un mecanismo clave para el polimorfismo concomitante.
- La diferencia de energía libre entre los polimorfos dicta la selectividad de la nucleación cruzada.
- Las simulaciones moleculares proporcionan información detallada sobre las vías complejas de cristalización.
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