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El salto de intercambio magnético fotoinducido promueve el estado fundamental de la polarización del espín de

Martin L Kirk^1,2,3,4, David A Shultz⁵, Anil Reddy Marri⁵

¹Department of Chemistry and Chemical Biology, The University of New Mexico, MSC03 2060, 1 University of New Mexico, Albuquerque, New Mexico 87131-0001, United States.

Journal of the American Chemical Society

|March 22, 2024

Resumen

La polarización de espín de electrones fotoinducida (ESP) se logró en complejos de platino con radicales de nitróxido de nitronilo. La magnitud de la ESP aumentó con la longitud del puente y estaba inversamente relacionada con el acoplamiento magnético, allanando el camino para la ciencia de la información cuántica.

Área de la Ciencia:

Química Inorgánica La Química Inorgánica es la química inorgánica.
La fotoquímica es la fotoquímica.
Ciencias de la información cuántica Ciencias de la información cuántica.

Sus antecedentes:

La polarización de espín de electrones (ESP) es crucial para el procesamiento de información cuántica.
Los radicales de nitróxido de nitronilo (NN) y los ligandos de catecolatos (CAT) son componentes clave en el magnetismo molecular.
Los complejos de platino (II) ofrecen propiedades electrónicas sintonizables para estudios fotofísicos.

Objetivo del estudio:

Para investigar la polarización de espín de electrones (ESP) fotoinducida en complejos Pt (II) que contienen radicales de nitróxido de nitronilo (NN).
Para correlacionar la magnitud ESP con las propiedades electrónicas y magnéticas de los complejos.
Explorar el potencial de estos sistemas para las aplicaciones de la ciencia de la información cuántica.

Principales métodos:

Síntesis de tres complejos Pt(II) con diferentes longitudes de puentes para-feniletinilo que conectan los radicales NN.
Espectroscopia de resonancia paramagnética de electrones de onda continua (cw-EPR) para caracterizar las propiedades magnéticas del estado fundamental.
La excitación láser pulsada (532 nm) y la espectroscopia EPR transitoria para observar el ESP inducido por la luz.

Principales resultados:

Se observó ESP fotoinducida en los estados electrónicos fundamentales de los tres complejos tras la excitación del cromóforo (CAT) Pt (bpy).
La magnitud de la ESP aumentó con el número de enlaces en el puente de feniletinilo (complejo 1 < 2 < 3).
La magnitud de la ESP estaba inversamente correlacionada con el acoplamiento de intercambio magnético del estado fundamental entre los radicales NN.

Conclusiones:

La excitación de un solo fotón puede inducir la polarización de espín en múltiples espines radicales dentro de los complejos Pt(II).
El ESP observado y su dependencia de la longitud del puente y el acoplamiento magnético ofrecen información sobre la dinámica de giro.
Estos hallazgos apoyan el desarrollo de protocolos ESP multi-qubit/qudit fotoinducidos para la ciencia de la información cuántica.

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