For a molecule, the phosphorescence lifetime without quenching is 1.0 s while with a quencher population of 10-2 M the phosphorescence lifetime is 0.10 s. Calculate the rate constant for phosphorescence assuming that kisc >> (kF + kec + kic). Calculate the rate constant for external conversion of the triplet state (kec’), the quenching rate constant for the triplet state (kq’), and the Stern-Volmer quenching constant. Assume that intersystem crossing from T1 to So is negligible.

For a molecule, the phosphorescence lifetime without quenching is 1.0 s while with a quencher population of 10-2 M the phosphorescence lifetime is 0.10 s. Calculate the rate constant for phosphorescence assuming that kisc >> (kF + kec + kic). Calculate the rate constant for external conversion of the triplet state (kec’), the quenching rate constant for the triplet state (kq’), and the Stern-Volmer quenching constant. Assume that intersystem crossing from T1 to So is negligible.

Principles of Instrumental Analysis

7th Edition

ISBN:9781305577213

Author:Douglas A. Skoog, F. James Holler, Stanley R. Crouch

Publisher:Douglas A. Skoog, F. James Holler, Stanley R. Crouch

Chapter12: Atomic X-ray Spectrometry

Section: Chapter Questions

Problem 12.12QAP

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For a molecule, the phosphorescence lifetime without quenching is 1.0 s while with a quencher population of 10^-2 M the phosphorescence lifetime is 0.10 s. Calculate the rate constant for phosphorescence assuming that k_isc >> (k_F + k_ec + k_ic). Calculate the rate constant for external conversion of the triplet state (k_ec’), the quenching rate constant for the triplet state (k_q’), and the Stern-Volmer quenching constant. Assume that intersystem crossing from T₁ to S_o is negligible.

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