A pulse radiolysis investigation of 9,10-diphenylanthracene excited state formation in 3-methylpentane at low temperature

The influence of temperature, down to 87 K, on the formation of excited states in the pulse radiolysis of 10⁻³ mol dm⁻³ 9,10-diphenylanthracene in 3-methylpentane was investigated. Lowering the temperature decreases the yield of solute singlets and triplets produced during the pulse and extends the time scale of excited state formation up to milliseconds or even seconds. This effect is mainly due to slower ionic reactions at low temperature. The ionic processes are responsible for the formation of about 70% of the solute singlets and all the triplets in pulse-irradiated 10⁻³ mol dm⁻³ 9,10-diphenylanthracene in 3-methylpentane.