photoionization detector http://msi-ontology.sourceforge.net/ontology/CHROM.owl#msi_01090 photoionization detector PID WEB:<http://www.chemistry.adelaide.edu.au/external/soc-rel/content/pid.htm> PERSON:Daniel Schober The selective determination of aromatic hydrocarbons or organo-heteroatom species is the job of the photoionization detector (PID). This device uses ultraviolet light as a means of ionizing an analyte exiting from a GC column. The ions produced by this process are collected by electrodes. The current generated is therefore a measure of the analyte concentration. f the amount of ionization is reproducible for a given compound, pressure, and light source then the current collected at the PID's reaction cell electrodes is reproducibly proportional to the amount of that compound entering the cell. The reason why the compounds that are routinely analyzed are either aromatic hydrocarbons or heteroatom containing compounds (like organosulfur or organophosphorus species) is because these species have ionization potentials (IP) that are within reach of commercially available UV lamps. The available lamp energies range from 8.3 to 11.7 ev, that is, lambda max ranging from 150 nm to 106 nm. Although most PIDs have only one lamp, lamps in the PID are exchanged depending on the compound selectivity required in the analysis. gas chromatography detector metadata complete