Resonance Raman characterization of the triplet state of zinc tetraphenylchlorin

Journal Article · Thu May 11 04:00:00 EDT 1995 · Journal of Physical Chemistry

DOI:https://doi.org/10.1021/j100019a006· OSTI ID:50775

Vitols, S E; Terashita, Shin Ichi; Blackwood, Jr, M E; Kumble, R; Ozaki, Y; Spiro, T G ^[1]

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1. Princeton Univ., NJ (United States)

The T{sub 1} excited state of zinc(II) tetraphenylchlorin, ZnTPC, has been studied by nanosecond time-resolved transient absorption (TA) and transient resonance Raman (TR{sup 3}) spectroscopy. The TA difference spectrum shows an induced absorption at 450 nm that is assigned as arising from a {sup 3}({pi},{pi}*) state. The most striking feature of the {sup 3}(ZnTPC) TR{sup 3} spectrum is the significant frequency downshifts and strong intensity enhancements of the pyrrole half-ring stretch, {nu}{sub 4}, and of other pyrrole ring motions which together produce a broad band in the 1150-1300-cm{sup -1} region. In addition, the enhancement of C{sub 12}C{sub m} modes ({nu}{sub 2} and {nu}{sub 11}) changes with their phasing between the S{sub 0} and T{sub 1} states. Weaker intensity enhancements, with no frequency shifts, are seen for the phenyl substituent ring mode, {Phi}{sub 4} and {nu}{sub 1}, and C{sub m}-phenyl stretch. These findings suggest that there is less electronic participation from the phenyl rings in the resonant triplet state, T{sub n}, for ZnTPC than for its parent metalloporphyrin, ZnTPP. 31 refs., 4 figs., 1 tab.

• Sponsoring Organization: USDOE
• DOE Contract Number: FG02-88ER13876
• OSTI ID: 50775
• Journal Information: Journal of Physical Chemistry, Journal Name: Journal of Physical Chemistry Journal Issue: 19 Vol. 99; ISSN JPCHAX; ISSN 0022-3654
• Country of Publication: United States
• Language: English

Related Subjects

40 CHEMISTRY
ABSORPTION SPECTRA
EXCITED STATES
GROUND STATES
ORGANOMETALLIC COMPOUNDS
PORPHYRINS
RAMAN SPECTRA
ZINC COMPOUNDS