Fluorescence Quenching Studies of 1,3‐Diphenyl Benzene

Abstract

Fluorescence quenching of 1,3‐diphenyl benzene (m‐terphenyl) by carbon tetrachloride (CCl4) at steady state in different solvents, namely n‐hexane, n‐heptane, cyclohexane, toluene, benzene acetonitrile, 1,4‐dioxane, and with a transient method in benzene has been done at room temperature to understand the role of quenching mechanisms. The Stern–Volmer plot was found to be linear for all the solvents studied. The probability of quenching per encounter p was determined in all the solvents and was found to be less than unity. Further, from the studies of rate parameters and lifetime measurements in benzene at different temperatures (30–60°C), it was shown that the phenomenon of quenching is generally governed by the well‐known Stern–Volmer (S‐V) plot. The activation energy E a (E′a) of quenching was determined using literature values of activation energy of diffusion E d, and it was found to be greater than E d, which confirms the fact that the quenching mechanism is not solely due to material diffusion but there is also contribution from activation energy.