Time-resolved microwave conductivity experiments

We have repeated the time resolved microwave conductivity experiments in the saturated hydrocarbons cyclohexane and trans-decalin and confirmed our previous results (De Haas et al., 1975 Warman et al., 1976 Anisimov et al., 1987). Both the electrons and holes formed on ionization have mobilities much larger than that for molecular ions and react very rapidly with certain impurities. In addition, in trans-decalin the hole has actually been found to become the major charge carrier below a temperature of 10 C. 

Time-resolved microwave conductivity measurements with electrodes in electrochemical cells can conveniently be made with pulsed lasers (e.g., an Nd-YAG laser) using either normal or frequency-doubled radiation. Instead of a lock-in amplifier, a transient recorder is used to detect the pulse-induced microwave reflection. While transient microwave experiments with semiconducting crystals or powders have been performed... 

The texture of the catalysts also controls the half-lifetime of charge carriers. This can be easily obtained from microwave absorption experiments using a time-resolved microwave conductivity... 

The seminal work of Marcus and Hush has had a significant impact on the development of PET. Pioneering efforts by Sutin, Hopfield, Jortner, and others established the connection between thermal electron transfer and photoelectron transfer [6]. This work set the stage for a notable series of experiments where laser flash spectroscopy [7], chemically induced nuclear polarization [8], resonance Raman spectroscopy [9], time-resolved microwave conductivity [10], and time-resolved photoacoustic calorimetry [11], to site only a few examples, have been successfully employed to chart the dynamics of PET in homogeneous solution, the solid-state, and organized assemblies. 

This is the first direct observation reported on a singlet diradical to zwitterion transition. The assignment of zwitterionic state stems from the dc and microwave time-resolved conductivity experiments. 

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