Vibrationally mediated photodissociation dynamics of pyrrole

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F19%3A10414683" target="_blank" >RIV/00216208:11320/19:10414683 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/61388955:_____/19:00517109

Výsledek na webu

<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=agiFv4W8ON" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=agiFv4W8ON</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1063/1.5091974" target="_blank" >10.1063/1.5091974</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Vibrationally mediated photodissociation dynamics of pyrrole

Popis výsledku v původním jazyce

We investigate photo dissociation of vibrationally excited pyrrole molecules in a velocity map imaging experiment with IR excitation of N-H bond stretching vibration v(1) = 1, nu(IR) = 3532 cm(-1), and UV photodissociation at lambda(UV) = 243 nm. In the IR+UV experiment, the H-fragment signal is enhanced with respect to the 243 nm UV-only photodissociation due to a more favorable Franck-Condon factor for the vibrationally excited molecule. In the measured H-fragment kinetic energy distribution, the maximum of the fast peak in the IR+UV experiment is shifted by 0.23 eV compared to the UV-only photodissociation which corresponds to 53 % of the vibrational energy deposited into the fragment kinetic energy. We compare our results with an isoenergetic UV-only photodissociation at lambda(UV) = 224 nm. About 72 % of the total available energy, is released into the fragment kinetic energy in the IR+UV experiment, while it is only 61 % in the UV-only photodissociation. This can be substantiated by the coupling of the N-H bond stretching vibration into the kinetic energy of the departing H-fragment. We also probe the time-dependent dynamics by a nanosecond pump-probe experiment. The IR excitation enhances the N-H bond dissociation even when the UV photodissociation is delayed by 150 ns. This enhancement increases also the yield of the fast fragments at the position of the peak corresponding to the IR+UV excitation, i.e. even 150 ns after the IR vibrational excitation, the same amount of the IR excitation energy can be converted into the H-fragment velocity as immediately after the excitation. (C) 2019 Author(s).

Název v anglickém jazyce

Vibrationally mediated photodissociation dynamics of pyrrole

Popis výsledku anglicky

We investigate photo dissociation of vibrationally excited pyrrole molecules in a velocity map imaging experiment with IR excitation of N-H bond stretching vibration v(1) = 1, nu(IR) = 3532 cm(-1), and UV photodissociation at lambda(UV) = 243 nm. In the IR+UV experiment, the H-fragment signal is enhanced with respect to the 243 nm UV-only photodissociation due to a more favorable Franck-Condon factor for the vibrationally excited molecule. In the measured H-fragment kinetic energy distribution, the maximum of the fast peak in the IR+UV experiment is shifted by 0.23 eV compared to the UV-only photodissociation which corresponds to 53 % of the vibrational energy deposited into the fragment kinetic energy. We compare our results with an isoenergetic UV-only photodissociation at lambda(UV) = 224 nm. About 72 % of the total available energy, is released into the fragment kinetic energy in the IR+UV experiment, while it is only 61 % in the UV-only photodissociation. This can be substantiated by the coupling of the N-H bond stretching vibration into the kinetic energy of the departing H-fragment. We also probe the time-dependent dynamics by a nanosecond pump-probe experiment. The IR excitation enhances the N-H bond dissociation even when the UV photodissociation is delayed by 150 ns. This enhancement increases also the yield of the fast fragments at the position of the peak corresponding to the IR+UV excitation, i.e. even 150 ns after the IR vibrational excitation, the same amount of the IR excitation energy can be converted into the H-fragment velocity as immediately after the excitation. (C) 2019 Author(s).

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10301 - Atomic, molecular and chemical physics (physics of atoms and molecules including collision, interaction with radiation, magnetic resonances, Mössbauer effect)

Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2019

Kód důvěrnosti údajů

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

Název periodika

AIP Advances [online]

ISSN

2158-3226

e-ISSN

—

Svazek periodika

9

Číslo periodika v rámci svazku

3

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

7

Strana od-do

035151

Kód UT WoS článku

000462880300099

EID výsledku v databázi Scopus

2-s2.0-85064668307