(a) Draw a Jablonski diagram for formaldehyde, indicating the photophysical processes that can take place and the molecular orbital involved in the transitions. Explain each process shown. (b) Explain with the aid of a suitable diagram why for an organic molecule the triplet state of a specific orbital configuration has a lower energy than the corresponding singlet state. (c) Calculate the molar absorptivity coefficient of fluorescein given, a concentration of 4.2 X 10 -5 M, a path length of 0.001 meters and an absorbance of 0.39 at 482nm. Hence estimate the quantum yield of fluorescence after excitation at this wavelength, given the initial intensity of the light (lo) was seen to be 10 times that of the subsequent fluorescence intensity (F1).

(a) Draw a Jablonski diagram for formaldehyde, indicating the photophysical processes that can take place and the molecular orbital involved in the transitions. Explain each process shown. (b) Explain with the aid of a suitable diagram why for an organic molecule the triplet state of a specific orbital configuration has a lower energy than the corresponding singlet state. (c) Calculate the molar absorptivity coefficient of fluorescein given, a concentration of 4.2 X 10 -5 M, a path length of 0.001 meters and an absorbance of 0.39 at 482nm. Hence estimate the quantum yield of fluorescence after excitation at this wavelength, given the initial intensity of the light (lo) was seen to be 10 times that of the subsequent fluorescence intensity (F1).

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

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