Hydrocarboxyl Radical as a Product of α-Alanine Ultraviolet Photolysis.
J Phys Chem Lett
; 12(50): 11992-11997, 2021 Dec 23.
Article
em En
| MEDLINE
| ID: mdl-34889613
ABSTRACT
UV photodissociation of α-alanine was studied by parahydrogen matrix isolation infrared spectroscopy. The temporal behavior of Fourier transform infrared spectra revealed that UV irradiation at 213 nm yielded the HOCO radical as a direct photoproduct from the S2 excited state. The concentration of HOCO quickly approached a steady state due to secondary photodissociation of HOCO to produce CO2 + H or CO + OH. On the other hand, no photoproducts were detected by S1 excitation at 266 nm. Irradiation of fully deuterated α-alanine at 213 nm yielded â¼2 times more cis-DOCO radicals than the lower energy isomer trans-DOCO, indicating that the conformation of the hydroxyl group is fairly well-preserved upon photodissociation of α-alanine. The present study suggests that HOCO may be a good tracer species in the search for amino acids in interstellar space.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Raios Ultravioleta
/
Dióxido de Carbono
/
Alanina
Idioma:
En
Ano de publicação:
2021
Tipo de documento:
Article