2003
Computer Modeling and Simulations on Flexible Bifunctional Systems: Intramolecular Energy Transfer Implications
VRBKA, Luboš, Petr KLÁN, Zdeněk KŘÍŽ, Jaroslav KOČA, Peter J. WAGNER et. al.Základní údaje
Originální název
Computer Modeling and Simulations on Flexible Bifunctional Systems: Intramolecular Energy Transfer Implications
Autoři
VRBKA, Luboš (203 Česká republika), Petr KLÁN (203 Česká republika, garant), Zdeněk KŘÍŽ (203 Česká republika), Jaroslav KOČA (203 Česká republika) a Peter J. WAGNER (840 Spojené státy)
Vydání
Journal of Physical Chemistry A, USA, The American Chemical Society, 2003, 1089-5639
Další údaje
Jazyk
angličtina
Typ výsledku
Článek v odborném periodiku
Obor
10401 Organic chemistry
Stát vydavatele
Spojené státy
Utajení
není předmětem státního či obchodního tajemství
Impakt faktor
Impact factor: 2.792
Kód RIV
RIV/00216224:14310/03:00008683
Organizační jednotka
Přírodovědecká fakulta
UT WoS
000182732800032
Klíčová slova anglicky
computational; simulation; flexibility; energy transfer
Štítky
Příznaky
Mezinárodní význam
Změněno: 9. 2. 2007 14:21, prof. RNDr. Petr Klán, Ph.D.
Anotace
V originále
The conformational search of the potential energy surface using the single coordinate driving method CICADA, molecular dynamics calculations, and quantum mechanical studies using the 6-31G* basis set were used for a detailed analysis of the conformational behavior of various flexible bichromophoric compounds Ph-CO-(CH2)x-O-Ar (x = 3-14; Ar = 2-naphthyl, 2-biphenylyl, 3-biphenylyl, 4-biphenylyl). The results were used for the estimation of the end-to-end intramolecular (exchange) energy transfer efficiency and for comparison to the data recently obtained from the steady-state quenching and quantum yield measurements (Wagner, P. J.; Klan, P. J. Am. Chem. Soc. 1999, 121, 9626-9635). The conformational search clearly supported the dominance of the through-space interaction in longer molecules (x = 5-14), which was still remarkably high even for x = 14. Comparing both computational and experimental results, a ~90% through-bond coupling was estimated for the shortest (x = 3) bichromophores. The molecular dynamics calculations seemed to validate the fact that only a small fraction of ground-state conformations involved ground-state control (static quenching) with the interchromophore distances within 4 Ĺ. Rate-determining bond rotations to such geometries should be then responsible for the energy transfer within the lifetime of the excited donor. The influence of chromophore orientation was found insignificant for long-tether molecules, but important in short-tether ones due to different reactive volumes of different acceptors, such as naphthalene or biphenyl. In addition, a correlation of the calculated average distances between the gamma-hydrogen and the carbonyl oxygen with the experimental hydrogen abstraction rate constants in the Norrish type II process strongly supported the right choice of the computational method.
Návaznosti
MSM 143100005, záměr |
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