A novel source of transient species for matrix isolation studies

A simple method for the production and cryogenic trapping of radicals and ions has been devised. The technique, acronymed CWRD (cold window radial discharge), enables the isolation in rare gas matrices of short-lived species formed within discharge plasmas, close to the trapping surface. Alternatively, the same apparatus can be employed to process with electrical discharges suitably doped rare gas solids, after standard deposition on a cold surface. The performance of this device has been tested in an experiment aimed at generating p-dichlorobenzene radical cation.