Conformational Control of the Photodynamics of a Bilirubin Dipyrrinone Subunit: Femtosecond Spectroscopy Combined with Nonadiabatic Simulations

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F60461373%3A22340%2F20%3A43920939" target="_blank" >RIV/60461373:22340/20:43920939 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/00216224:14310/20:00117372

Výsledek na webu

<a href="https://pubs.acs.org/doi/10.1021/acs.jpca.0c08945" target="_blank" >https://pubs.acs.org/doi/10.1021/acs.jpca.0c08945</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1021/acs.jpca.0c08945" target="_blank" >10.1021/acs.jpca.0c08945</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Conformational Control of the Photodynamics of a Bilirubin Dipyrrinone Subunit: Femtosecond Spectroscopy Combined with Nonadiabatic Simulations

Popis výsledku v původním jazyce

The photochemistry of bilirubin has been extensively studied due to its importance in the phototherapy of hyperbilirubinemia. In the present work, we investigated the ultrafast photodynamics of a bilirubin dipyrrinone subunit, vinylneoxanthobilirubic acid methyl ester. The photoisomerization and photocyclization reactions of its (E) and (Z) isomers were studied using femtosecond transient absorption spectroscopy and by multireference electronic structure theory, where the nonadiabatic dynamics was modeled with a Landau–Zener surface hopping technique. The following picture has emerged from the combined theoretical and experimental approach. Upon excitation, dipyrrinone undergoes a very fast vibrational relaxation, followed by an internal conversion on a picosecond time scale. The internal conversion leads either to photoisomerization or regeneration of the starting material. Further relaxation dynamics on the order of tens of picoseconds was observed in the ground state. The nonadiabatic simulations revealed a strong conformational control of the photodynamics. The ultrafast formation of a cyclic photochemical product from a less-populated conformer of the studied subunit was predicted by our calculations. We discuss the relevance of the present finding for the photochemistry of native bilirubin. The work has also pointed to the limits of semiclassical nonadiabatic simulations for simulating longer photochemical processes, probably due to the zero-point leakage issue.

Název v anglickém jazyce

Conformational Control of the Photodynamics of a Bilirubin Dipyrrinone Subunit: Femtosecond Spectroscopy Combined with Nonadiabatic Simulations

Popis výsledku anglicky

The photochemistry of bilirubin has been extensively studied due to its importance in the phototherapy of hyperbilirubinemia. In the present work, we investigated the ultrafast photodynamics of a bilirubin dipyrrinone subunit, vinylneoxanthobilirubic acid methyl ester. The photoisomerization and photocyclization reactions of its (E) and (Z) isomers were studied using femtosecond transient absorption spectroscopy and by multireference electronic structure theory, where the nonadiabatic dynamics was modeled with a Landau–Zener surface hopping technique. The following picture has emerged from the combined theoretical and experimental approach. Upon excitation, dipyrrinone undergoes a very fast vibrational relaxation, followed by an internal conversion on a picosecond time scale. The internal conversion leads either to photoisomerization or regeneration of the starting material. Further relaxation dynamics on the order of tens of picoseconds was observed in the ground state. The nonadiabatic simulations revealed a strong conformational control of the photodynamics. The ultrafast formation of a cyclic photochemical product from a less-populated conformer of the studied subunit was predicted by our calculations. We discuss the relevance of the present finding for the photochemistry of native bilirubin. The work has also pointed to the limits of semiclassical nonadiabatic simulations for simulating longer photochemical processes, probably due to the zero-point leakage issue.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10403 - Physical chemistry

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2020

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Journal of Physical Chemistry A

ISSN

1089-5639

e-ISSN

—

Svazek periodika

124

Číslo periodika v rámci svazku

50

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

15

Strana od-do

"10457–10471"

Kód UT WoS článku

000608855900006

EID výsledku v databázi Scopus

2-s2.0-85097740567