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Determinación precisa de la estructura atómica en 3D de los materiales amorfos

Yuxuan Liao¹, Haozhi Sha¹, Colum M O'Leary¹

¹Department of Physics and Astronomy and California NanoSystems Institute, University of California, Los Angeles, CA, USA.

|January 28, 2026

Resumen

La tomografía de electrones atómicos (AET) ahora permite el mapeo atómico 3D de materiales amorfos. Este estudio presenta un flujo de trabajo cuantitativo para la identificación y posicionamiento atómico preciso en estructuras no cristalinas.

Área de la Ciencia:

Ciencia de los materiales Ciencia de los materiales.
Nanotecnología La nanotecnología es la nanotecnología.
Ciencia de datos Ciencia de datos.

Sus antecedentes:

Los materiales amorfos carecen de orden de largo alcance, lo que limita la determinación de la estructura atómica en 3D.
A pesar de los avances, la determinación experimental de los arreglos atómicos 3D en materiales amorfos sigue siendo un desafío.
La tomografía atómica por electrones (TEA) ofrece una vía directa para el mapeo atómico en 3D.

Objetivo del estudio:

Presentar un análisis cuantitativo y un flujo de trabajo para AET en materiales amorfos.
Establecer métodos fiables para determinar las coordenadas atómicas 3D y las identidades elementales.
Proporcionar puntos de referencia para lograr un AET preciso de materiales no cristalinos.

Principales métodos:

Desarrolló un flujo de trabajo completo de AET que incluye el preprocesamiento de imágenes, la desinformación, la alineación, la reconstrucción, el rastreo de átomos y el refinamiento.
Se utilizaron conjuntos de datos simulados por múltiples cortes de nanopartículas amorfas de Si, SiGeSn y CoPdPt.
Comparó el rendimiento del flujo de trabajo con un enfoque alternativo bajo diferentes niveles de ruido.

Principales resultados:

El flujo de trabajo AET presentado permite la determinación confiable de coordenadas atómicas 3D e identidades elementales.
Se logra una alta precisión en la identificación de átomos (por ejemplo, 95,1% de Co, 99,0% de Pd, 100% de Pt en CoPdPt).
Se ha demostrado una alta precisión posicional 3D (por ejemplo, 29 pm para Co, 12 pm para Pd, 6 pm para Pt en CoPdPt).

Conclusiones:

El estudio establece directrices prácticas y puntos de referencia cuantitativos para un AET preciso de materiales amorfos.
El marco desarrollado proporciona un método robusto para la reconstrucción 3D de alta fidelidad en sistemas no cristalinos.
El enfoque es ampliamente aplicable a otras modalidades de imágenes tomográficas.

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