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Updated: Dec 10, 2025

Determination of the Photoisomerization Quantum Yield of a Hydrazone Photoswitch

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A Master Equation for Photochemical Rates.

James R Bolton¹

¹Bolton Photosciences Inc., Edmonton, AB, Canada.

Photochemistry and Photobiology

|September 1, 2020

Summary

Researchers developed a master equation to analyze photochemical reactions across all chromophore concentrations. This new equation allows for more accurate determination of incident photon flux and quantum yield using data from any concentration.

Area of Science:

Photochemistry
Chemical Kinetics

Background:

The general photochemical rate equation was previously integrable only at high or low chromophore concentration limits.
This limitation restricted the utilization of experimental data for deriving key reaction parameters.

Purpose of the Study:

To develop a unified photochemical rate equation applicable to all chromophore concentrations.
To enable the use of comprehensive concentration data for photochemical analysis.

Main Methods:

Integration of the general photochemical rate equation.
Derivation of a novel master equation.

Main Results:

A master equation valid for any chromophore concentration has been successfully derived.

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Last Updated: Dec 10, 2025

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Recombination Dynamics in Thin-film Photovoltaic Materials via Time-resolved Microwave Conductivity

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This equation overcomes the limitations of previous high and low concentration approximations.

Conclusions:

The new master equation allows for the utilization of data across all concentrations to determine incident photon flux and quantum yield.
Future photochemical studies using monochromatic light can benefit from this generalized approach.