UV-VIS ABSORPTION STUDIES OF SINGLET TO TRIPLET INTERSYSTEM CROSSING RATES OF AROMATIC KETONES - EFFECTS OF MOLECULAR-GEOMETRY

Authors
MCGARRY PF DOUBLEDAY CE WU CH STAAB HA TURRO NJ
Citation
Pf. Mcgarry et al., UV-VIS ABSORPTION STUDIES OF SINGLET TO TRIPLET INTERSYSTEM CROSSING RATES OF AROMATIC KETONES - EFFECTS OF MOLECULAR-GEOMETRY, Journal of photochemistry and photobiology. A, Chemistry, 77(2-3), 1994, pp. 109-117
Citations number
43
Categorie Soggetti
Chemistry Physical
Journal title
Journal of photochemistry and photobiology. A, Chemistry → ACNP
ISSN journal
10106030
Volume
77
Issue
2-3
Year of publication
1994
Pages
109 - 117
Database
ISI
SICI code
1010-6030(1994)77:2-3<109:UASOST>2.0.ZU;2-5
Abstract
The effect of the molecular geometry of diaryl and arylalkyl ketones o n the rate of intersystem crossing (ISC) was investigated by employing picosecond pump-probe studies of the growth of triplet-triplet absorp tions at 532 and 355 nm. Vibrational relaxation within the triplet man ifold was found to interfere with measurement of the ISC rates for cer tain benzophenone derivatives. The observed rapid decay of absorption at 355 nm is attributed to relaxation of vibrationally excited triplet s. The trends observed are consistent with direct singlet-to-triplet I SC from S1 to T1.