2014
Molecular Mechanism of Diaminomaleonitrile to Diaminofumaronitrile Photoisomerization: An Intermediate Step in the Prebiotic Formation of Purine Nucleobases
SZABLA, Rafal Kazimierz, Robert W. GÓRA, Jiří ŠPONER a Judit ŠPONEROVÁZákladní údaje
Originální název
Molecular Mechanism of Diaminomaleonitrile to Diaminofumaronitrile Photoisomerization: An Intermediate Step in the Prebiotic Formation of Purine Nucleobases
Autoři
SZABLA, Rafal Kazimierz (616 Polsko), Robert W. GÓRA (616 Polsko), Jiří ŠPONER (203 Česká republika, garant, domácí) a Judit ŠPONEROVÁ (348 Maďarsko, domácí)
Vydání
Chemistry - A European Journal, Weinheim, WILEY- VCH VERLAG GMBH, 2014, 0947-6539
Další údaje
Jazyk
angličtina
Typ výsledku
Článek v odborném periodiku
Obor
10403 Physical chemistry
Stát vydavatele
Německo
Utajení
není předmětem státního či obchodního tajemství
Odkazy
Impakt faktor
Impact factor: 5.731
Kód RIV
RIV/00216224:14740/14:00075641
Organizační jednotka
Středoevropský technologický institut
UT WoS
000331729700018
Klíčová slova anglicky
isomerization; nucleobases; nucleotides; photochemistry; quantum chemistry
Štítky
Příznaky
Mezinárodní význam, Recenzováno
Změněno: 10. 6. 2014 11:00, Martina Prášilová
Anotace
V originále
The photoinduced isomerization of diaminomaleonitrile (DAMN) to diaminofumaronitrile (DAFN) was suggested to play a key role in the prebiotically plausible formation of purine nucleobases and nucleotides. In this work we analyze two competitive photoisomerization mechanisms on the basis of state-of-the-art quantum-chemical calculations. Even though it was suggested that this process might occur on the triplet potential-energy surface, our results indicate that the singlet reaction channel should not be disregarded either. In fact, the peaked topography of the S-1/S-0 conical intersection suggests that the deexcitation should most likely occur on a sub-picosecond timescale and the singlet photoisomerization mechanism might effectively compete even with a very efficient intersystem crossing. Such a scenario is further supported by the relatively small spin-orbit coupling of the S-1 and T-2 states in the Franck-Condon region, which does not indicate a very effective triplet bypass for this photoreaction. Therefore, we conclude that the triplet reaction channel in DAMN might not be as prominent as was previously thought.
Návaznosti
ED1.1.00/02.0068, projekt VaV |
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