The photolysis of chloropicrin (CCl3NO2) was investigated in Ar and N-2 cryogenic matrices. The extent of reaction was monitored using FT-IR spectroscopy. Phosgene and nitrosyl chloride were the observed photoproducts at all wavelengths investigated (220, 251, 313, 365, and 405 nm). When the photolysis was performed with 220, 251, or 313 nm light, two additional bands were also observed. These bands have been assigned to CCl3ONO. Chloropicrin was also photolyzed in the presence of O-2 and O-18(2). O-18-labeled photoproducts were not detected in cryogenic matrices. (C) 2002 Elsevier Science B.V. All rights reserved.