ABSTRACT
Intense and analytically useful direct chemiluminescence (CL) has been observed from a rather limited group of organic compounds. These include diacylhydrazides, indoles, acridines and acridans, polydimethylaminoethylenes, anthracenes, and aroyl peroxides. A substantial number of other kinds of compounds, when
oxidized, give rise directly to very weak or ultraweak CL, which, if not analyti cally useful in and of itself, may provide excited states of lifetime sufficiently long as to sensitize intense fluorescence in an acceptor fluorophore by energy transfer. In addition, a number of compounds, such as dioxetanes, organic oxa lates, and oxamides, that are not necessarily chemiluminescent themselves can be thermally oxidized to electronically excited intermediates (aldehydes and ke tones) whose lifetimes in the excited state are sufficient for transfer of their excita tion energy to a suitable acceptor fluorophore to occur. These will be the subjects of this chapter.