Kinetic Parameters of Photo-Excited Triplet State of Pentacene Determined by Dynamic Nuclear Polarization

2015 ◽  
Vol 84 (4) ◽  
pp. 044005 ◽  
Author(s):  
Tomomi Kawahara ◽  
Satoshi Sakaguchi ◽  
Kenichiro Tateishi ◽  
Tsz Leung Tang ◽  
Tomohiro Uesaka
Keyword(s):  
Triplet State ◽  
Kinetic Parameters ◽  
Dynamic Nuclear Polarization ◽  
Nuclear Polarization ◽  
Excited Triplet State ◽  
Excited Triplet

Study of Chemically Induced Dynamic Nuclear Polarization of Aliphatic Aldehydes in D2O and other Solvents

1975 ◽  
Vol 53 (17) ◽  
pp. 2548-2557 ◽  
Author(s):  
Holger E. Chen ◽  
Michael Cocivera ◽  
Shiv P. Vaish
Keyword(s):  
Triplet State ◽  
Dynamic Nuclear Polarization ◽  
Nuclear Polarization ◽  
Hydrogen Abstraction ◽  
The Other ◽  
Excited Triplet State ◽  
Relative Importance ◽  
Aliphatic Aldehydes ◽  
Excited Triplet ◽  
Chemically Induced

The chemically induced dynamic nuclear polarization arising from irradiation of aliphatic aldehydes in D2O and various other solvents is reported. The aldehydes included acetaldehyde, propionaldehyde, isobutyraldehyde, and pivalaldehyde, and the solvents were benzene, acetonitrile, cyclohexane, methylcyclohexane, perfluoromethylcyclohexane, D2O, and D2O/acetonitrile. For propionaldehyde, the variation of c.i.d.n.p. with solvent can be explained by a variation of the relative importance of α-cleavage vs. hydrogen abstraction which occur via an excited triplet state. In addition, when D2O is the solvent, the c.i.d.n.p. provides information about secondary radical reactions not observed in the other solvents. For the other aldehydes, the nature of the solvent does not seem to affect the relative importance of α-cleavage vs. hydrogen abstraction. Acetaldehyde undergoes hydrogen abstraction whereas isobutyraldehyde and pivalaldehyde undgero α-cleavage via an excited triplet state.

Kinetic model for the molecular system of Zinc(II)-2,9,16,23-phthalocyanine tetracarboxylate

2015 ◽  
Vol 24 (01) ◽  
pp. 1550005 ◽  
Author(s):  
Saleh Al-Omari
Keyword(s):  
Kinetic Model ◽  
Triplet State ◽  
Kinetic Parameters ◽  
Ground State ◽  
Singlet State ◽  
Excited Singlet State ◽  
Excited Triplet State ◽  
Initial Population ◽  
Excited Singlet ◽  
Excited Triplet

Using vis absorption, fluorescence spectral experimental data, and time-resolved measurement, we have examined the kinetics of Zinc(II)-2,9,16,23-phthalocyanine tetracarboxylate ( ZnPc ( COONa )4), which is interesting photosensitizer of far red-absorption in water: NaOH solution. The kinetic parameters were measured and/or calculated. The photophysical properties originate principally from the planar macrocycle while the outer substituent and degree of carboxylation seem not to have a considerable influence on the kinetic parameters. The nonradiative rate constants of the first excited state were dominant due to the heavy metal effect. Using the obtained photophysical parameters, the population dynamics were calculated by kinetic model. On nanosecond scale of 15 ns, about 63% population of the first excited-singlet state is retrieved by the ground state. Whereas, the rest of population are deactivated to the first excited-triplet state. Later on, during about 7 μs starting from the initial decay of the first excited singlet state, the first excited singlet state and the first excited triplet state were completely empty, meanwhile the ground state retrieved its initial population. Due to the fact that ZnPc ( COONa )4 has strong absorption, long lifetimes of the first singlet and triplet excited states, and fast intersystem crossing, it may be suitable for nonlinear optical studies.

Aromaticity Reversal in the Lowest Excited Triplet State of Archetypical Möbius Heteroannulenic Systems

2016 ◽  
Vol 128 (22) ◽  
pp. 6597-6601 ◽  
Author(s):  
Juwon Oh ◽  
Young Mo Sung ◽  
Woojae Kim ◽  
Shigeki Mori ◽  
Atsuhiro Osuka ◽  
...  
Keyword(s):  
Triplet State ◽  
Excited Triplet State ◽  
Excited Triplet

scholarly journals TRANSIENT RAMAN SPECTRA OF ALL-TRANS- AND 9-CIS-RETINAL IN THE EXCITED TRIPLET STATE

1984 ◽  
Vol 13 (4) ◽  
pp. 549-550 ◽  
Author(s):  
Hiro-o Hamaguchi ◽  
Hiromi Okamoto ◽  
Mitsuo Tasumi
Keyword(s):  
Triplet State ◽  
Raman Spectra ◽  
Excited Triplet State ◽  
Excited Triplet
Sign in / Sign up

Export Citation Format

Share Document