Naslov
Comparative study of the photodynamics of malonaldehyde and acetylacetone

Autori
Sapunar, Marin ; Ayari, Tarek ; Došlić, Nađa

Izvornik
Chemical physics (0301-0104) 515 (2018); 622-627

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
malonaldehyde ; photochemistry

Sažetak
In this computational study we explore the photodynamics of malonaldehyde and compare it to that of the homologous acetylacetone. Upon photoexcitation to the bright S2(ππ*) state malonaldehyde relaxes to the S1(nπ*)state on an ultrashort time scale. Once in the S1(nπ*) state the population of malonaldehyde splits. Part of the population undergoes internal conversion to the ground state by deplanarization of the H- chelate ring, while the other part crosses to the triplet manifold. The comparison with acetylacetone reveals a substantial increase of the internal conversion pathways, from less than 20% in acetylacetone to 40% in malonaldehyde. We show that the substitution of the aliphatic hydrogens by the methyl groups reduces the accessibility of the S1/S0 conical intersection seam in acetylacetone. The system then crosses to the triplet manifold and homolytic C–CH3 bond cleavage takes place.

Izvorni jezik
Engleski

Znanstvena područja
Kemija

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