Laser photolysis studies on triplet-equilibrium formation in a small triplet-energy gap system

Autor:	Minoru Yamaji, Bronislaw Marciniak, Haruo Shizuka, Katsuji Okada
Rok vydání:	1997
Předmět:	chemistry.chemical_compound Laser photolysis Chemistry Band gap Dibenzothiophene Energy transfer Enthalpy Benzophenone Analytical chemistry General Physics and Astronomy Flash photolysis Physical and Theoretical Chemistry Acetonitrile
Zdroj:	Scopus-Elsevier
ISSN:	0009-2614
DOI:	10.1016/s0009-2614(97)00902-0
Popis:	Formation of a triplet-equilibrium between benzophenone (BP) and dibenzothiophene (DBT) was studied in acetonitrile by 355 nm laser flash photolysis. The triplet-equilibrium constant ( K eq = 1.7) was determined at 295 K as well as the absolute rate constants for triplet energy transfer from BP to DBT ( k f = 3.1 × 10 9 M −1 s −1 ) and back triplet-energy transfer ( k b = 2.0 × 10 9 M −1 s −1 ) whose ratio ( k f / k b ) was in agreement with the K eq value. It was revealed that the triplet-equilibrium formation in the BP-DBT system was promoted by the entropy change ( ΔS = 2.0 cal mol −1 K −1 ) rather than the enthalpy change ( ΔH = 0.3 kcal/mol).
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_dedup___::9a2a5e563c03490af20ffa72e54ffd8d https://doi.org/10.1016/s0009-2614(97)00902-0 Zobrazit plný text záznamu Full Text from ScienceDirect