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Una herramienta de diseño in silico para el cruce de espín de Fe(II) y los complejos atrapados por estado de espín
Robert J Deeth1, Anna E Anastasi, Martin J Wilcockson
1Inorganic Computational Chemistry Group, Department of Chemistry, University of Warwick, Coventry CV4 7AL, UK. r.j.deeth@warwick.ac.uk
Journal of the American Chemical Society
|May 4, 2010
Resumen
Nuevos métodos computacionales aceleran el descubrimiento de los materiales de cruce de espín (SCO) y atrapamiento de estado de espín excitado inducido por la luz (LIESST). La mecánica molecular de campo de ligando empírico (LFMM) ofrece una alternativa más rápida y precisa al DFT para diseñar nuevos complejos de coordinación.
Área de la Ciencia:
- Química computacional es la química computacional.
- Ciencia de los materiales ciencia de los materiales.
- La química de la coordinación es química de la coordinación.
Sus antecedentes:
- El descubrimiento de nuevos materiales de cruce de espín (SCO) y atrapamiento de estado de espín excitado inducido por la luz (LIESST) requiere herramientas computacionales eficientes.
- La teoría funcional de densidad (DFT) proporciona precisión, pero es demasiado lenta para el descubrimiento molecular a gran escala.
Objetivo del estudio:
- Introducir y validar la mecánica molecular empírica de campo de ligando (LFMM) como un método computacional más rápido para el descubrimiento de materiales SCO / LIESST.
- Demostrar la utilidad de LFMM en el rediseño de sistemas existentes para nuevas propiedades SCO/LIESST.
Principales métodos:
- Se empleó la mecánica molecular de campo de ligando empírico (LFMM) para modelar los efectos d-electrón.
- Los cálculos de LFMM se llevaron a cabo en complejos simples de Fe (II) am (m) minas.
- Comparación de la velocidad y precisión de LFMM con DFT.
Principales resultados:
- LFMM es hasta 4 órdenes de magnitud más rápido que DFT.
- El LFMM captura con precisión los efectos de los electrones d que son cruciales para los fenómenos SCO y LIESST.
- LFMM permitió el rediseño de complejos conocidos para producir potenciales nuevos materiales SCO y LIESST.
Conclusiones:
- LFMM presenta un avance significativo para el descubrimiento computacional de materiales SCO y LIESST.
- Este método acelera la exploración del espacio químico para nuevos complejos de coordinación funcional.
- LFMM facilita el diseño racional de materiales con las propiedades deseadas de conmutación del estado de espín.
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