Chemiluminescence of UV-irradiated linolenic acid and squalene.

An emission spectral analysis was carried out on ultraweak chemiluminescence emitted from UVB-irradiated linolenic acid and squalene. The main emission species produced by the transition of (1 delta g) (1 delta g) dimer and an additional weak band near 477.5 nm (0, 0) by the transition of (1 delta g (1 epsilon g+) to (3 epsilon g-) (3 epsilon g-) were found by spectroscopic analysis of chemiluminescence in both cases of irradiated linolenic acid and of squalene. A distinct peak around 410-420 nm was observed in irradiated squalene and the emitter seems to be due to the excited carbonyl compound.