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Control de la fotoquímica a través de los isótopos y la preexcitación IR

Daniela Kern-Michler¹, Carsten Neumann¹, Nicole Mielke¹

¹Institute of Biophysics, Goethe University Frankfurt , Max-von-Laue-Str. 1, 60438 Frankfurt am Main, Germany.

Journal of the American Chemical Society

|November 29, 2017

Resumen

Los investigadores desarrollaron una secuencia de pulsos ultra rápida para desencadenar selectivamente reacciones fotoquímicas en moléculas específicas, incluso aquellas con espectros UV-Vis idénticos. Este avance permite la fotoquímica selectiva de isótopos y abre las puertas a nuevas aplicaciones en espectroscopia y desenjaulado.

Área de la Ciencia:

Química
Espectroscopia
La fotoquímica

Sus antecedentes:

Distinguir y reaccionar selectivamente moléculas similares es un desafío debido a la superposición de espectros de absorción UV-Vis.
Los isótopos, moléculas que difieren solo en la masa atómica, poseen espectros UV-Vis casi idénticos, lo que dificulta la manipulación fotoquímica selectiva.

Objetivo del estudio:

Para demostrar la fotoquímica selectiva de las especies usando una nueva secuencia de pulsos ultrarrápidos.
Para superar las limitaciones de la espectroscopia UV-Vis en la diferenciación de moléculas similares para el control fotoquímico.

Principales métodos:

Utilizó la secuencia de pulsos de resonancia electrónica impulsada por vibración (VIPER).
Diferencias aprovechadas en los espectros infrarrojos para la discriminación de especies, permitiendo la excitación electrónica selectiva.

Principales resultados:

Se ha logrado una fotoquímica selectiva por isótopos en solución para moléculas con espectros UV-Vis indistinguibles.
Se ha demostrado la capacidad de inducir y controlar reacciones fotoquímicas específicas basadas en frecuencias vibratorias.

Conclusiones:

La secuencia de pulsos VIPER permite un control sin precedentes sobre la fotoquímica para moléculas espectralmente similares.
Las aplicaciones futuras incluyen el fotoenvejecimiento ortogonal y la espectroscopia selectiva de especies en mezclas complejas.

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