I have plotted a Stern-Volmer Plot but cannot work out the fluorescence lifetime to be able to get the rate constant [closed]








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I have plotted a stern Volmer plot and have my straight line equation. I understand that the gradient is kqtf but I need tf to work out kq but I don't have kd to do 1/kd.


How do I work it out?




In a Stern-Volmer plot the ratio of fluorescence yield $\varphi$ is plotted vs the quencher concentration $[Q]$ as $\varphi\_0/\varphi\_Q =1 +k\_{SV}[Q] $ where the gradient is the quenching constant which is $k\_2\tau$ where $k\_2$ is the 2nd order rate constant and $\tau$ the fluorescence decay in the absence of quenching.


(If you search this site you will find examples <https://applying-maths-book.com/intro.html> )


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