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Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
Published on: June 28, 2018
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Conjunto completo de módulos elásticos de un sólido de espín cruzado: dependencia del estado de espín y accionamiento
Mirko Mikolasek1, Maria D Manrique-Juarez2,3, Helena J Shepherd4
1ESRF-The European Synchrotron , 71 Avenue des Martyrs , 38000 Grenoble , France.
Journal of the American Chemical Society
|June 20, 2018
Resumen
Este estudio revela cómo los complejos de cruce de espín molecular
Área de la Ciencia:
- Ciencias de los materiales
- Química del estado sólido
- Mecánica
Sus antecedentes:
- Los complejos de cruce de espín molecular (SCO) son prometedores para la activación mecánica.
- Comprender el vínculo entre la estructura cristalina de SCO y las propiedades mecánicas es crucial pero desafiante.
- La investigación existente carece de datos completos sobre el comportamiento mecánico de los complejos SCO en condiciones variables.
Objetivo del estudio:
- Para determinar las propiedades mecánicas del complejo de cruce de espín [FeII(HB(tz) 3].
- Investigar la influencia de las transiciones de estado de espín en el comportamiento mecánico de los complejos SCO.
- Para correlacionar la anisotropía de la estructura cristalina con la compresibilidad de la celosía y la respuesta mecánica.
Principales métodos:
- Difracción de rayos X sincrotrón de alta presión.
- Es una dispersión nuclear inelástica.
- Mediciones micromecánicas (a granel y con película delgada).
Principales resultados:
- El módulo de volumen (B) se determinó en 11,5 ± 1,5 GPa, el módulo de Young (Y) en 10,9 ± 1,0 GPa, y el coeficiente de Poisson (ν) en 0,34 ± 0,04.
- El análisis de la estructura cristalina reveló la compresibilidad anisotrópica de la celosía relacionada con el espaciamiento molecular y las interacciones C-H·N.
- La transición del espín de un estado de espín bajo a un estado de espín alto causó una caída significativa en el módulo de Young a 7.1 ± 0.5 GPa.
Conclusiones:
- El estudio establece las principales propiedades mecánicas del complejo [FeII(HB(tz) 3) 2 SCO.
- La compresibilidad anisotrópica está directamente relacionada con la estructura cristalina y las interacciones intermoleculares.
- La disminución observada en el módulo de Young en la transición de giro destaca el potencial de activación mecánica conmutable.
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