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Dinámica semiclásica de todos los átomos estudio de la coherencia cuántica en el complejo fotosintético
Hyun Woo Kim1, Aaron Kelly, Jae Woo Park
1Institute of Theoretical and Computational Chemistry, Department of Chemistry, Pohang University of Science and Technology, Pohang 790-784, Korea.
Journal of the American Chemical Society
|June 20, 2012
Resumen
Los complejos fotosintéticos de recolección de luz muestran coherencia cuántica en la transferencia de energía. El entorno proteico mantiene acoplamientos electrónicos, lo que permite una transferencia de energía eficiente incluso con mutaciones, cruciales para la comprensión de estos sistemas naturales.
Área de la Ciencia:
- La investigación de la fotosíntesis en la investigación de la fotosíntesis.
- La biología cuántica es la biología cuántica.
- La biofísica es la biofísica.
Sus antecedentes:
- Los complejos fotosintéticos pigmento-proteína facilitan la transferencia de energía de excitación (EET).
- Se ha observado coherencia cuántica en EET, pero su papel y la influencia de la proteína siguen siendo objeto de debate.
- Comprender la coherencia de alta temperatura es clave para desbloquear mecanismos eficientes de transferencia de energía.
Objetivo del estudio:
- Investigar el papel del entorno proteico y los modos vibratorios en la coherencia EET.
- Explorar el alcance de la coherencia a alta temperatura en los complejos fotosintéticos.
- Aclarar los mecanismos que mantienen la coherencia en el complejo Fenna-Matthews-Olson.
Principales métodos:
- Empleado un marco semiclásico con una descripción de todos los átomos del complejo fotosintético.
- Estudió la transferencia de energía de excitación en el complejo Fenna-Matthews-Olson.
- Analizó el impacto de los modos vibratorios, la modulación electrostática de las proteínas y las mutaciones en la coherencia.
Principales resultados:
- Las vibraciones de los cromóforos disminuyen la coherencia a nivel de conjunto, pero se observa una coherencia más larga a nivel de un solo complejo.
- Las oscilaciones coherentes en las poblaciones del sitio ocurren dentro de decenas de femtosegundos.
- La proteína mantiene acoplamientos electrónicos, e incluso las mutaciones conservan un acoplamiento y coherencia significativos.
Conclusiones:
- El entorno proteico es crucial para mantener los acoplamientos electrónicos y la coherencia en EET.
- Tanto las fuerzas de acoplamiento de cromóforos como sus fluctuaciones son esenciales para comprender la EET coherente.
- Las vías coherentes de transferencia de energía exhiben redundancia debido a las fluctuaciones térmicas.
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