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Superátomo de alto espín estabilizado por el relleno de doble subcapa

Dinesh Bista¹, Alexander P Aydt², Kevin J Anderton³

¹Department of Physics, Virginia Commonwealth University, Richmond, Virginia 23220, United States.

Journal of the American Chemical Society

|March 15, 2022

Resumen

Los investigadores descubrieron que los grupos de calogenuro de metales de transición específicos con doble relleno de subcapa electrónica exhiben una notable estabilidad y momentos magnéticos de alto espín. Este hallazgo abre nuevas vías para diseñar superátomos magnéticos estables.

Área de la Ciencia:

* La nanociencia y la química de los materiales
* Química Cuántica y Teoría del Superátomo

Sus antecedentes:

* El confinamiento cuántico en pequeños cúmulos conduce al llenado de capas electrónicas, creando superátomos con mayor estabilidad.
* Los grupos de metal de transición octaédricos pueden lograr configuraciones estables con 100 o 114 electrones de valencia.

Objetivo del estudio:

* Para predecir teóricamente y verificar experimentalmente un cúmulo superatómico que combina alta estabilidad y magnetismo de alto espín.
* Investigar el papel del relleno de doble subcapas en el logro de estas propiedades en grupos de metal de transición calogenuro.

Principales métodos:

* Cálculos teóricos de las estructuras electrónicas y de la estabilidad.
* Síntesis experimental y caracterización de un nuevo grupo, [NEt4]5[Fe6S8(CN) 6].
* Mediciones de las propiedades magnéticas y análisis de la estructura electrónica.

Principales resultados:

* Se ha demostrado que un grupo con 107 electrones de valencia logra un doble llenado de subcapas (57 + 50 electrones).
* Se confirmó una alta estabilidad y un momento magnético de alto espín (S = 7/2) en el racimo sintetizado.
* Mostró una estructura electrónica totalmente deslocalizada en el nuevo superátomo.

Conclusiones:

* La primera evidencia computacional y experimental de la importancia del llenado dual de subcapas en grupos de calogenuros de metales de transición.
Se estableció una nueva clase de superátomos magnéticos estables de alto espín con aplicaciones potenciales en la ciencia de los materiales.

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