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Acceso a los estados propios de espín-1/2 desconectados de larga duración a través de espines > 1/2

Kevin Claytor¹, Thomas Theis, Yesu Feng

¹Department of Physics, ‡Department of Chemistry, §Duke Small Molecule Synthesis Facility, ∥Department of Radiology, and ⊥Department of Biomedical Engineering, Duke University , Durham, North Carolina 27708, United States.

Journal of the American Chemical Society

|September 18, 2014

Resumen

Los núcleos de spin-1/2 químicamente equivalentes pueden formar estados de larga vida. El acoplamiento con deuterio (un spin > 1/2 núcleo) permite la transferencia de población a estos estados, ofreciendo potencial para el almacenamiento de polarización.

Área de la Ciencia:

Espectroscopia de Resonancia Magnética Nuclear (RMN) Espectroscopía de Resonancia Magnética Nuclear (RMN) Espectroscopía de Resonancia Magnética Nuclear (RMN) Espectroscopía de Resonancia Magnética Nuclear (RMN) Espectroscopía de Resonancia Magnética Nuclear (RMN) Espectroscopía de Resonancia Magnética Nuclear (RMN) Espectroscopía de Resonancia Magnética Nuclear (RMN) Espectroscopía de Resonancia Magnética Nuclear (RMN) Espectroscopía de Resonancia Magnética Nuclear (RMN) Espectroscopía de Resonancia Magnética Nuclear (RMN) Espectroscopía de Resonancia Magnética Nuclear (RMN)
Ciencias de la información cuántica Ciencias de la información cuántica.
Química Física es la química física.

Sus antecedentes:

Los pares de núcleos de spin-1/2 químicamente equivalentes pueden formar estados cuánticos de larga duración.
Estos estados exhiben vidas significativamente más largas que la magnetización convencional.
Las interacciones cuatrupolares de núcleos con espín > 1/2 generalmente inducen una rápida relajación.

Objetivo del estudio:

Extender las clases conocidas de moléculas con estados accesibles de larga vida.
Investigar el papel del deuterio (espín > 1/2) en el acceso a estados de larga vida en sistemas con pares de espín 1/2.
Explorar el potencial de estos estados para el almacenamiento de polarización.

Principales métodos:

Análisis teórico de la dinámica de espín.
Experimentos de Resonancia Magnética Nuclear (RMN) en las pruebas de resonancia nuclear.
Investigando acoplamientos escalares entre núcleos de deuterio y carbono-13.

Principales resultados:

Demostró que el acoplamiento de deuterio puede facilitar la transferencia de población a estados de larga vida.
Se demostró que estos estados de larga vida son resistentes a los mecanismos de relajación dominantes.
Confirmado que la simple deuteración de moléculas con abundancia natural de pares de carbono-13 es suficiente para mediciones de por vida.

Conclusiones:

Las moléculas con pares de carbono-13 directamente unidos al deuterio son candidatos prometedores para el almacenamiento de polarización.
Los acoplamientos escalares pueden superar la relajación rápida típicamente inducida por los núcleos cuadrupolares.
Esta investigación abre nuevas vías para la utilización de los estados de larga vida en RMN.

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